Cavity wall insulation invoice template UK (2026): CIS, VAT Notice 708/6 and stage payments
A cavity wall insulation invoice has to explain what was surveyed, drilled, filled, made good and handed over - not a vague "cavity done" or "walls insulated" line. "Supply and install cavity wall insulation as agreed" does not tell a householder whether they got bonded polystyrene beads, mineral wool blown fill, a named foam system, how many elevations were treated, whether airbricks and flues were checked and left clear, or how drill holes were re-pointed and colour-matched. It does not tell a main contractor's QS which plot, purchase order or fabric package to release. It does not tell a CIS contractor how much is labour and how much is the direct cost of beads, wool, foam, mortar, plugs and making-good materials you paid for.
Cavity wall insulation is fabric and finishing work for heat-loss reduction through masonry cavities, not a full external render package, not loft insulation at joist level, and not a decorative facade job. Mentions of a plasterer, scaffolder or render installer on this page are contrasts and cross-links - the subject here is cavity fill (survey, drill, inject/blow, make-good, ventilation and flue checks) with the product and elevation narrative that make the job readable. Soft landscaping and driveway surfaces belong elsewhere.
Who pays matters. Billing a private householder for cavity wall insulation on their own home: normal invoice, no CIS. Billing a main contractor, developer, housing association principal or refurbishment contractor for fitting thermal insulation: often CIS when the work sits inside a wider construction / alteration package. HMRC's CISR14240 is the lead reference: fitting of thermal insulation, lagging or soundproofing as part of a wider project of construction is within CIS; fitting in premises not undergoing construction where this has no effect on the fabric of the building is outside. Soften absolute claims - the facts matter. Cavity fill that drills masonry and re-points holes typically does affect the fabric, which is why contractor-paid cavity programmes often sit firmly inside CIS finishing operations when they form part of a wider construction or alteration package. Fabric alteration context can also touch CISR14100 (buildings and structures), but lead with CISR14240 for the insulation fitting itself. Supply-only materials sit outside under CISR14220; supply-plus-install can pull the whole payment into CIS (CISR14020 / CISR14030). Private householders are not CIS contractors - see CISR12030 and the public CIS overview.
VAT is closer to the loft insulation, heat pump and solar guides than to ordinary decorative fabric pages. For qualifying residential (and relevant charitable) installs of energy-saving materials including insulation for walls, VAT Notice 708/6 sets a zero rate from 1 May 2023 to 31 March 2027 (then toward 5% - check the live notice nearer the time). Soften: notice conditions must be met; InvoiceAdept does not decide VAT status. Distinguish carefully: cavity fill as insulation can sit inside the energy-saving materials relief when conditions are met; a decorative render, cladding or paint finish on its own is not automatically the same relief - do not stretch Notice 708/6 onto decorative works that are not the installation of energy-saving materials. Supply without install is usually standard-rated. Never invent 0% for commercial, hospital or hotel installs outside scope. Never reverse-charge a householder. Domestic reverse charge does not apply to zero-rated supplies.
This guide gives copy-paste fields, a labour/materials split for cavity wall packages (including deposits before ordering bead, wool or foam volumes), stages from survey through drill/fill, make-good and snag/handover, four worked examples and a practical treatment of CIS, VAT Notice 708/6 and domestic reverse charge. Figures are illustrative only, not UK market rates or a price list. InvoiceAdept does not decide CIS or VAT status and does not file CIS300, VAT returns, Making Tax Digital updates or Self Assessment to HMRC. It does not issue Building Control certificates, CIGA / guarantee agency paperwork, ECO4 or Great British Insulation Scheme (GBIS) grant forms, or damp / ventilation certificates. Describe suitability, ventilation and flue caveats on the invoice only as job narrative - this page is not install advice and not a substitute for competent-person, manufacturer or guarantee-scheme guidance.
Related templates: loft insulation, render, plasterer, how to invoice a client (UK tradesperson), calculate retention payments, deposit invoice, domestic reverse charge and late payment rights. This page covers cavity fill (bead, mineral wool, named foam systems) with drill/make-good - not external wall insulation (EWI) boards as a cladding system, and not a full render package.
Rules and links were checked for this guide on 9 September 2026. General information only, not tax, legal, Building Regulations, grant, damp diagnosis, ventilation design or install certification advice. InvoiceAdept is from Tech Me Today Ltd, Companies House 15917255, ICO ZB944663.
In short
Start by identifying who pays you, whether the walls are suitable cavity masonry (not solid wall, not already filled without assessment), which product family you are installing (beads, mineral wool, named foam), which elevations are in scope, whether materials must be ordered before work starts, and whether the contract is supply-only or supply-and-install.
Private householder, own-home cavity wall insulation: no CIS. If VAT-registered and the install qualifies under Notice 708/6, the zero rate can apply from 1 May 2023 to 31 March 2027 when conditions are met - then check the live notice (framework points toward 5%). Show product type, elevations / coverage narrative, drill and make-good, airbrick / flue checks, waste and snag. Never invent commercial 0%. Never reverse-charge a householder.
Cavity wall insulation for a CIS contractor: often within CIS for fitting of thermal insulation as part of a wider project of construction (CISR14240). Soften where premises are not undergoing construction and there is no fabric effect - though drill-and-fill typically does affect fabric. Split labour from materials at direct cost (CISR15060 / CISR15090).
Materials only (no install): generally outside CIS (CISR14220). Supply-plus-install can pull the whole contract into CIS (CISR14020 / CISR14030).
VAT zero rate (Notice 708/6): only when residential/charitable conditions are met, to 31 March 2027, for qualifying insulation installs. Do not stretch the relief onto decorative render or cladding that is not energy-saving materials installation. Supply-only is usually standard-rated. Reverse charge does not apply to zero-rated supplies.
Guarantees / grants (CIGA-type / ECO4 / GBIS): check live scheme rules; do not invent grant amounts. The invoice is not the guarantee certificate and not the grant form.
Take a deposit before ordering large material volumes if your terms require one. Stage survey, drill/fill, make-good and snag/handover. Keep variations separate.
Use the invoice generator for a first invoice. InvoiceAdept Free is £0 for five invoices per month. Pro is £7.99 excl VAT and includes WhatsApp send. Pro+ is £12.99 excl VAT and includes CIS. Stripe's own fees apply (UK cards 1.5%+20p), but InvoiceAdept adds no platform fee.
Who this cavity wall insulation invoice template is for
This template is for UK cavity wall insulation installers, insulation subcontractors, fabric builders who include cavity fill in residential packages, and energy-efficiency firms who need readable invoices for householders, landlords, contractors and housing clients. It covers the paperwork pattern, not a price list and not a Building Control, CIGA, ECO4 or damp-diagnosis document.
Cavity wall insulation installers (bead, mineral wool blown fill, named foam systems)
Insulation subcontractors delivering domestic and small multi-unit packages who still need clear invoice lines
Builders and developers who include cavity fill on new plots, refurbs or fabric programmes
Render firms who add cavity fill as a separate fabric line before or beside render - keep the products distinct on the invoice
Plasterers making good internal patches after accidental blow-through or after related fabric works
Loft insulation firms who package loft and cavity as separate clear lines on one energy upgrade
Subcontractors to main contractors on residential fabric / energy packages
Sole traders and limited companies who need CIS and VAT lines that match the payer
If your day job is external wall insulation boards as a cladding system, a full silicone / acrylic render package with no cavity fill, or loft-only insulation, use those related guides and come back here for cavity-fill-specific lines (product type, elevations, drill/make-good, airbrick/flue narrative and Notice 708/6 VAT notes).
How this differs from loft insulation, render and plasterer guides
Guide | Focus | Use this cavity wall page when... |
|---|---|---|
Cold loft, warm roof, blown loft fibre | The product is cavity fill in masonry walls, not loft insulation | |
External render systems, base coats, finishes | Cavity fill is the defined insulation product, not the decorative/weathering render | |
Plaster, skim, making good | Internal making-good is only part of a wider cavity invoice | |
General UK trades invoicing pattern | You need cavity-specific CIS, Notice 708/6 and drill/fill lines | |
Retention maths and release invoices | A contractor package withholds retention on cavity fabric works | |
This page | Dedicated cavity wall insulation invoicing | Survey, drill, inject/blow, make-good and flue/airbrick narrative are the product |
Do not duplicate an entire render or loft guide here. Mentions of silicone top coats or loft boarding are contrasts only - keep them off a cavity-only invoice unless they were part of the agreed package.
Three cavity wall jobs, three invoices
These three jobs can use similar materials but need different invoice logic.
Domestic householder cavity fill | Contractor insulation package | Materials-only / supply-only caution | |
|---|---|---|---|
Customer on invoice | Private householder | Builder, developer, housing principal or fabric contractor | Builder, merchant customer or householder |
Contract | Survey, drill, fill, make-good, snag | Fabric / energy package to named plots or addresses | Supply beads / bags / drums delivered; no install |
CIS | No. Householder is not a CIS contractor. | Often within CIS when fitting thermal insulation as part of a wider construction project - CISR14240; soften if premises not undergoing construction and no fabric effect (drill-and-fill usually affects fabric) | Generally outside CIS (CISR14220) - unless mixed with install |
Labour/materials | Helpful for clarity | Essential for correct deduction; beads/wool/foam/mortar at direct cost | Materials supply lines; no CIS labour block |
VAT if registered | Often 0% under Notice 708/6 for qualifying residential insulation install to 31 Mar 2027 when conditions met; else check notice | Normal VAT, zero rate if still qualifying, or reverse charge only on standard-rated eligible supplies | Usually standard-rated supply without install |
Key references | Notice 708/6 insulation for walls; public CIS guide; householder not contractor | CISR14240; CISR14100 context; CISR15060/15090; CISR14020/14030 if mixed | CISR14220; CISR14020 / CISR14030 if later install added |
What often bounces it | "Walls done" with no product, elevations, stage or deposit credit; inventing 0% for commercial; inventing ECO4 £ amounts; selling the PDF as a CIGA certificate | Missing UTR, plot/PO, labour/material split; claiming free-issue beads as your materials; CIS on householder-direct work | Treating supply-only as CIS labour; then adding install under same contract without revisiting mixed rules |
A main contractor can be the CIS contractor even when the finished walls serve a tenant or homeowner. If the builder engages you, your invoice is to that builder. That contractor-to-subcontractor payment is the one to test. If the householder hires and pays you directly, the householder invoice has no CIS.
Cavity fill product types to describe on the invoice
Name the product family so a QS, householder or future surveyor can see what was actually installed.
Type | Useful invoice words | Avoid |
|---|---|---|
Bonded polystyrene beads | Bead system name/family if known; bonded; elevations treated; coverage narrative | "Premium eco beads" with no elevations or product family |
Mineral wool blown cavity fill | Wool family; blown into cavity; elevations; density narrative if on PO | Vague "wool in walls" with no elevations |
Named foam / expanding foam systems | System name as installed; elevations; curing / make-good note | Marketing "magic foam" with no product identity |
Partial fill / top-up where factual | Existing fill noted; additional treatment scope | Silent top-up that looks like a first-time empty cavity without saying so |
Extraction / remedial (if in package) | Failed fill removed; waste; re-fill as separate stage | Pretending extraction is a free survey |
Make-good / re-point | Hole count narrative or elevation make-good; mortar colour match note | Full facade re-point billed as "make-good" |
What cavity wall insulation work belongs on the invoice
Name the work so a QS, householder or future buyer can see what was actually installed.
Line group | Typical inclusions | Do not bury here |
|---|---|---|
Survey / suitability | Cavity inspection, borescope notes, exposure / damp caveats as narrative, quote reference | A silent "survey fee" with no visit or deliverable; a damp specialist report you did not write |
Prep / protection | Scaffold or access if in package; protection to paths / windows; cavity barriers check narrative | Full scaffold hire billed as insulation without a scaffold line |
Product supply | Beads, wool, foam, mortar, plugs, tapes at direct cost | Free-issue materials from the main contractor |
Drill / inject / blow | Drill pattern; fill method; elevations treated | Whole-house loft fill billed as cavity work |
Airbricks / flues / vents | Checked and left clear if factual; replacements if in package | Install design advice presented as a combustion safety certificate |
Make-good | Re-point drill holes; colour match; clean-down | Full elevation re-point or render you did not deliver |
Internal making-good | Patch after blow-through if agreed; plasterer pass-through if separate | Full room skim you did not deliver |
Waste | Drill spoil, packaging, old fill if extracted | Van stock you did not buy for this address |
Variations | Agreed extras coded V01, V02 with written approval | Silent bumps inside "additional wall works" |
The invoice is not a Building Control certificate, not a CIGA / guarantee document, not an ECO4 / GBIS form and not a damp or ventilation design report. Describe caveats; do not certify what you are not authorised to certify.
Cavity fill jobs often sit near combustion appliances, airbricks and extract ducts. On the invoice you can narrate what you agreed to check or leave clear - for example airbricks left open, flues checked clear, or vents not blocked. Soften absolute claims. This guide does not tell you how to design or certify combustion safety. Do not sell the PDF as a Gas Safe certificate, PAS evidence or Building Regulations completion. If another firm designs or tests ventilation, keep their paperwork separate and do not invent their results on your invoice.
What a UK cavity wall insulation invoice must include
GOV.UK is narrower than most blogs. You must give a VAT invoice by law when both you and the customer are VAT-registered. If you are not registered, keep numbered records of what you charged - which is also how you get paid.
A unique identification number
Your name (or company name), address and contact information
The customer's name and address
A clear description of what you are charging for (address, product type, elevations / coverage, stage)
The date the goods or service were provided (supply date) and the date of the invoice
The amount being charged, the VAT amount if applicable (including 0% with the right narrative when Notice 708/6 applies), and the total amount owed
Sole trader with a trading name: show your own name and a serviceable address. Limited company: registered name, company number and registered office. The VAT registration threshold is £90,000, not the stale £85,000 figure. For a cavity wall insulation invoice, a clear description is what gets you paid, so name the site address, product type, elevations or coverage narrative and stage (deposit / survey / drill-fill / make-good / completion).
CIS lines (UTR, labour, materials, rate, deduction, net payable) belong when a contractor is paying you under the scheme - not on a private householder job. Domestic reverse charge wording belongs only when the VAT reverse-charge tests are actually met between VAT-registered construction businesses on standard-rated supplies - never on a householder bill, and not on zero-rated Notice 708/6 lines. See domestic reverse charge.
For the general pattern of raising readable UK trades invoices, see how to invoice a client (UK tradesperson).
Copy-paste cavity wall insulation invoice fields
Use these as a checklist when you raise the PDF or app invoice.
Field | Example (illustrative) |
|---|---|
Invoice number | CW-2026-0142 |
Invoice date | 9 September 2026 |
Supply / tax point | 6 September 2026 (or deposit date if deposit) |
From | Your legal name / Ltd name, address, company number if Ltd, VAT number if registered |
Bill to | Householder name + site address, or contractor legal name + accounts email + PO |
Site address | 12 Example Road, Town, Postcode (if different from bill-to) |
PO / plot | PO-7781 / Plot 14 (contractor jobs) |
Description | Cavity wall insulation - bonded polystyrene bead fill to front, rear and side elevations; drill, inject, make-good and re-point; airbricks and flues checked clear; waste removal and handover at [address] |
Labour | Survey support, drill, inject/blow, make-good, snag (split for CIS) |
Materials | Beads / wool / foam, mortar, plugs, fixings at direct cost |
Deposit credit | Less deposit CW-2026-0138 £450 (illustrative) |
VAT | 0% Notice 708/6 if qualifying residential insulation install and conditions met; else as applicable; never invent commercial 0%; do not stretch onto decorative-only render |
Due date | 23 September 2026 |
Payment | Sort code / account / reference, or Stripe card link |
CIS block | Only if contractor-paid and CIS applies: UTR, CIS base, rate, deduction, net |
Sole trader versus limited company
Sole trader: show your own legal name (trading name optional), a serviceable address, VAT only if registered (threshold £90,000), your UTR when CIS applies, and bank details in your name.
Limited company: show the registered company name, Companies House number, registered office, VAT only if the company is registered, company UTR when CIS applies, and a company bank account matching the invoice name.
Do not invoice as "Ali Cavity Fillers" without the legal entity that actually contracted. Card payments and CIS statements get messy when the name on the invoice is not the payee.
Labour versus materials for cavity wall CIS
When CIS applies, split lines so deduction sits on the right base.
Category | Typical cavity wall contents | CIS note |
|---|---|---|
Labour | Survey support, drill, inject/blow, make-good, re-point, snag | Usually in the CIS deduction base when the operation is in scope |
Materials at direct cost | Beads, mineral wool, foam, mortar, plugs, tapes you bought | Deduction usually excludes materials at direct cost - CISR15060 / CISR15090 |
Free-issue materials | Beads or bags supplied by the main contractor | Do not list as your materials |
Plant / access | Tower hire ticket if separate; scaffold erect/dismantle if in package | Keep hire tickets visible |
Mark-up | Your profit | Do not hide mark-up inside "materials" to shrink labour |
Tickets win disputes. Keep merchant invoices matched to the job address or PO.
What cavity wall job types to describe
Job type | Description tips | CIS / VAT reminder |
|---|---|---|
First-time bead fill (empty cavity) | Empty / suitable cavity noted; bead family; elevations | Householder: no CIS; often Notice 708/6 0% if qualifying to Mar 2027 |
Mineral wool blown fill | Wool family; elevations; coverage narrative | Same householder / contractor split; do not invent grant £ |
Named foam system | System identity; elevations; make-good | CISR14240 when part of wider construction; VAT still Notice 708/6 if qualifying insulation |
Remedial extraction then re-fill | Extraction stage separate from re-fill stage | Do not blur failed-fill removal into a silent survey |
Partial elevations only | Name which elevations are in / out of scope | Avoid "whole house" wording if only two elevations were treated |
Make-good-only add-on | Hole count / elevation make-good after another firm's fill | Soften CIS / VAT - may not be the same as full ESM install |
Materials delivery only | Product list and delivery address | Usually outside CIS (CISR14220); usually standard-rated VAT |
Deposits and stages for multi-day cavity jobs
Many single-dwelling cavity fills finish in a day; larger multi-property packages, remedial extraction-and-refill jobs and scaffolding-heavy elevations often need stages.
Stage | Typical trigger | Invoice tip |
|---|---|---|
Deposit | Acceptance before ordering large bead / wool / foam volumes | Numbered deposit invoice; credit later |
Survey / suitability | Inspection complete; written scope confirmed | Photos and borescope notes help disputes |
Drill / fill | Elevations drilled and filled | Name product and elevations again |
Make-good / snag | Holes re-pointed; clean-down; agreed snags closed | Final balance less deposits and retentions |
Retention is not a deposit. Deposit is money you take before or during. Retention is money held after completion against snagging. Show full value, retention withheld and release date, then invoice retention when it falls due. See calculate retention payments for the maths pattern. A deposit you receive is a VAT tax point for that amount on the day it lands if you are registered - apply the correct rate (including 0% when Notice 708/6 genuinely applies to that supply).
See the deposit invoice template for deposit-only PDFs.
Example stage payment schedule (illustrative)
ILLUSTRATIVE only - not a market survey. Shows how a multi-day householder or small contractor package might be staged.
Stage | Illustrative share | What the invoice should say |
|---|---|---|
Deposit | 20% (£400 on a £2,000 example package) | Deposit against cavity fill at [address]; product family noted |
Survey / materials on site | 20% (£400) | Survey complete; materials delivered; credit deposit on later final |
Drill and fill complete | 40% (£800) | Elevations named; product named; photos optional attachment note |
Make-good and handover | 20% (£400) | Re-point complete; airbricks/flues narrative; snag closed; balance less deposits |
CIS: thermal insulation under CISR14240 (and related refs)
For contractor-paid work, start with CISR14240: finishing operations include fitting of thermal insulation, lagging or soundproofing as part of a wider project of construction. Soften absolute claims - the facts of the contract matter.
The same manual also lists as outside construction operations: fitting of thermal insulation or soundproofing in premises not undergoing construction where this has no effect on the fabric of the building. Cavity wall insulation that drills masonry and re-points holes typically does affect the fabric of the building. That is why contractor-paid cavity programmes often sit inside CIS when they form part of a wider construction or alteration package - but still test the facts. Do not auto-CIS every invoice without reading who pays and what the contract covers.
Fabric alteration / repair context can also engage CISR14100 (buildings and structures - construction, alteration, repair). Lead with CISR14240 for the insulation fitting itself; cite CISR14100 where the wider package is clearly alteration or repair of the building.
Situation | Typical CIS direction (soften; test facts) |
|---|---|
Main contractor pays you to fit cavity insulation on plots as part of a build / refurb package | Often within CIS as thermal insulation finishing (CISR14240) |
Housing principal pays you inside a wider fabric alteration programme | Often within CIS when part of wider construction / alteration (CISR14240; CISR14100 context) |
Private householder hires and pays you directly for own-home cavity fill | No CIS - householder is not a CIS contractor |
You only deliver beads / bags; another firm installs | Generally outside CIS for your supply (CISR14220) |
Supply-and-install under one contractor contract | Mixed rules - CISR14020 / CISR14030 can pull the whole payment into CIS when fitting is in scope |
Soft insulation in premises not undergoing construction with no fabric effect | Manual points outside - rarely a good fit for drill-and-fill; test carefully; do not stretch |
Related heating / ventilation system install under same contractor | May also engage CISR14090 for those systems - cavity insulation itself still leads on CISR14240 |
Materials at direct cost: CISR15060 / CISR15090. Who is not a contractor: householder context under the public CIS guide and CISR12030.
CIS deduction rates (when CIS applies): commonly 20% for verified subcontractors and 30% for unverified - check the live HMRC CIS rate that applies to that subcontractor. Do not invent rates. Gross payment status is a separate verification outcome. InvoiceAdept does not decide CIS status.
CIS yes/no quick map for cavity wall invoices
Payer | Work | CIS on your invoice? |
|---|---|---|
Private householder (own home) | Drill, fill, make-good | No |
Private landlord paying you directly as householder-style client | Same | Usually no CIS contractor relationship - test facts; do not invent |
Main contractor / developer | Cavity fill as part of construction / alteration package | Often yes (CISR14240) |
Housing association as principal contractor-style engager | Programme of fills | Often yes when they are a CIS contractor for the works |
Merchant / householder | Materials delivery only | Usually no (CISR14220) |
Main contractor | Supply-and-install under one contract | Often yes for the whole payment when fitting in scope (CISR14020/14030) |
VAT Notice 708/6: zero rate for qualifying cavity wall insulation
This is the section that differs most from ordinary decorative fabric trade pages and aligns with the loft insulation guide. Read it slowly.
Under VAT Notice 708/6, installation of certain energy-saving materials - including insulation for walls - in residential accommodation (and relevant charitable buildings under the notice) can be zero-rated from 1 May 2023 to 31 March 2027 when notice conditions are met. From 1 April 2027 the framework points back toward the 5% reduced rate - check the live notice nearer the time. Soften: InvoiceAdept does not decide whether your supply qualifies.
Insulation means materials designed and installed because of their insulating qualities - wall insulation is expressly listed in section 2.10 of Notice 708/6.
The relief applies to the services of installing energy-saving materials, and to the supply of those materials by the person who installs them.
Supply without installation is usually standard-rated.
Caution: do not stretch Notice 708/6 onto decorative render, paint, cladding or weathering finishes that are not the installation of energy-saving materials. A cavity fill and a silicone render are different products - invoice them separately and test VAT on each supply.
When energy-saving materials are installed with other works, test whether you have a single supply or mixed supplies (Notice 708/6 section 2.5). An extension build with incidental insulation can be a single standard-rated construction supply - do not force 0% onto the whole extension because insulation was included.
Never invent 0% for commercial warehouses, hotels or hospitals outside residential/charitable scope.
Never reverse-charge a householder.
Domestic reverse charge does not apply to zero-rated supplies.
Supply | Typical VAT direction (soften; test notice) |
|---|---|
Qualifying residential cavity wall insulation install (Notice 708/6 conditions met), to 31 Mar 2027 | Often 0% |
Same after the zero-rate window closes | Framework toward 5% - check live notice |
Supply of beads / wool / foam without install | Usually standard-rated |
Decorative render / cladding only (not ESM install) | Do not force Notice 708/6 0% - usually standard-rated unless another relief truly applies |
Commercial / out-of-scope install | Do not force 0% |
Insulation incidental inside a single standard-rated extension package | May follow the principal construction supply - test section 2.5; do not overclaim |
Domestic reverse charge on standard-rated CIS construction between eligible parties | Show VAT, do not add it to the amount they pay - and remember reverse charge does not apply to zero-rated lines |
Never tell a commercial client their warehouse walls are "VAT free because insulation is zero-rated" without checking scope. Never reverse-charge a private individual. Prefer cautious accurate wording over overclaiming reduced or zero rates.
VAT rate comparison table (illustrative caution)
Scenario | Likely rate to test | Caution |
|---|---|---|
Householder, qualifying residential cavity fill, May 2023 to Mar 2027 | 0% if Notice 708/6 met | Conditions + residential/charitable scope |
Same from 1 Apr 2027 | Framework toward 5% | Check live notice |
Materials sold over the counter, no install | 20% | Supply without install |
Pure decorative render on occupied dwelling | Usually 20% | Not automatic ESM |
Hotel / hospital / prison install | Usually 20% | Outside residential ESM list in the notice |
Not VAT-registered trader | No VAT on invoice | Threshold £90,000 |
ECO4, GBIS, CIGA-type guarantees - check scheme rules
Energy-efficiency schemes such as ECO4 and the Great British Insulation Scheme (GBIS) change. Guarantee agencies such as CIGA (Cavity Insulation Guarantee Agency) also have their own paperwork. Soften absolute claims. This guide does not invent grant amounts, income thresholds, measure scores or guarantee premiums. If a specific scheme contribution or guarantee reference is a factual part of how that job is paid or handed over, you may narrate a scheme reference on client paperwork - but:
Do not invent market-wide "typical ECO4 £" or "typical cavity fill cost" survey figures on the invoice or in this article
Do not treat the invoice as the grant application, measure evidence or guarantee certificate
Do not delay your due date to "when the grant pays" unless your written terms say so
Check live scheme rules on official publications when you need numbers
InvoiceAdept does not issue ECO4, GBIS, TrustMark, PAS or CIGA paperwork.
Supply-only versus supply-and-install
Pattern | CIS direction (typical) | VAT direction (typical) |
|---|---|---|
Deliver beads / bags only | Outside CIS - CISR14220 | Usually standard-rated |
Supply and install under one contract | Mixed rules - CISR14020/14030 can pull whole payment into CIS when fitting is in scope | Often Notice 708/6 analysis if residential qualifying insulation install |
Install labour only; free-issue materials | Labour in CIS base when fitting in scope (CISR14240) | Still test Notice 708/6 on the labour/install supply |
Make-good / re-point only add-on | Soften - may still be finishing works when part of wider construction | Soften - may not automatically inherit ESM zero rate for every mortar line |
Domestic reverse charge note for contractor-paid cavity insulation
Critical for cavity wall insulation: if your residential install is correctly zero-rated under Notice 708/6, domestic reverse charge does not apply to that zero-rated supply. If the customer is a private householder, reverse charge does not apply anyway. Reverse charge only becomes relevant between eligible VAT-registered construction businesses on standard-rated supplies that meet the reverse-charge tests - for example some commercial or otherwise non-zero-rated contractor chains. See the domestic reverse charge guide. Soften and test facts; InvoiceAdept does not decide reverse-charge status.
Worked examples A-D
Example A - Householder bonded bead fill on occupied home (no CIS, Notice 708/6 zero rate)
ILLUSTRATIVE. Assumes VAT-registered installer and a qualifying residential insulation install meeting Notice 708/6 conditions within the 1 May 2023 to 31 March 2027 window.
Line | Amount |
|---|---|
Labour - survey support, drill, inject bonded beads to four elevations, make-good, snag | £1,050 |
Materials - beads, mortar, plugs, fixings at direct cost | £720 |
Airbrick replacements (2no) if in package | £60 |
Subtotal | £1,830 |
VAT at 0% (Notice 708/6 qualifying - illustrative assumption) | £0 |
Total due | £1,830 |
CIS | None - private householder |
Example B - Householder mineral wool fill with deposit and stages (no CIS)
ILLUSTRATIVE. Householder; stages; VAT shown as 0% only as an illustrative Notice 708/6 assumption for a qualifying residential insulation install.
Stage | What to show | Note |
|---|---|---|
Deposit CW-2026-0201 | £400 before ordering wool / materials | Tax point on deposit day if VAT-registered |
Stage CW-2026-0208 | Survey + drill/fill to named elevations | Credit deposit; show product family |
Final CW-2026-0211 | Make-good, clean-down, snag; balance | Less deposits |
VAT | 0% if qualifying Notice 708/6; else as applicable | Soften - test facts |
CIS | None | Householder-direct |
Example C - Contractor-paid cavity fill on refurb plots (verified 20% CIS)
ILLUSTRATIVE only. Verified subcontractor at 20%. Treat figures as VAT-exclusive for clarity. Assumes fitting of thermal insulation as part of a wider project of construction (CISR14240 in scope).
Line | Amount |
|---|---|
Labour - drill, fill, make-good, snag across Plots 3-5 | £3,600 |
Materials - beads / wool / mortar at direct cost | £2,400 |
CIS labour base | £3,600 |
CIS deduction at 20% | £720 |
Materials (no CIS deduction on direct cost) | £2,400 |
Net payable after CIS | £5,280 before any VAT treatment |
Do not claim free-issue beads as materials. Do not shrink labour by stuffing mark-up into materials. Soften VAT on the contractor invoice separately - residential qualifying zero rate, commercial standard rate, or reverse charge only where tests are met on standard-rated lines.
Example D - Materials-only delivery (no install)
ILLUSTRATIVE. Supply of bonded beads and mortar bags delivered to site; no fitting labour.
Line | Amount |
|---|---|
Materials - beads and mortar delivered | £980 |
CIS | Generally none on pure manufacture/delivery - CISR14220 |
VAT | Usually standard-rated supply without install |
If install is later added under the same contract, revisit mixed-contract rules (CISR14020 / CISR14030) and VAT Notice 708/6 before the next invoice.
Example E - Contractor package with 5% retention (illustrative)
ILLUSTRATIVE. Shows retention presentation - not advice on whether retention is fair.
Line | Amount |
|---|---|
Gross value - cavity fill Plots 1-2 (ex VAT for clarity) | £4,000 |
Retention withheld 5% | £200 |
Due now (less retention) | £3,800 |
Retention release date (contract diary) | e.g. 6 months after practical completion |
Later retention invoice | £200 when release falls due |
See calculate retention payments for the release invoice pattern.
Mistakes that bounce cavity wall insulation invoices
Mistake | Why it bounces | Fix |
|---|---|---|
"Walls done" with no product or elevations | QS / householder cannot match the quote | Name product family, elevations, drill/make-good, stage |
CIS on a private householder | Householder is not a CIS contractor | Remove CIS block; normal invoice |
Inventing ECO4 / GBIS £ amounts | Fake stats and grant mis-selling risk | Check live scheme rules; narrate references only when factual |
Claiming 0% VAT on a commercial warehouse cavity fill | Outside residential/charitable ESM scope | Standard rate unless another relief truly applies |
Stretching Notice 708/6 onto decorative render | Render is not automatic energy-saving materials install | Invoice render separately; test VAT on each supply |
Reverse charge on a zero-rated 708/6 supply | Reverse charge does not apply to zero-rated lines | Use correct zero-rate narrative instead |
Free-issue materials listed as yours | Inflates materials; understates labour | Invoice labour only for free-issue kit |
Supply-only treated as CIS labour | CISR14220 keeps delivery outside | Materials invoice without CIS labour block |
Auto-CIS every cavity job without CISR14240 facts | Who pays and wider project facts matter | Test payer + wider construction / fabric-effect facts |
Using £85,000 as VAT threshold | Outdated | Use £90,000 |
Selling the invoice as a CIGA, ventilation or grant certificate | It is not | Keep certificates and grant forms separate |
"Whole house" when only two elevations were filled | Scope dispute | Name elevations in / out of scope |
Late payment: contractor debts are not consumer debts
Commercial late payment interest for qualifying business debts sits on Bank Rate plus 8%. With Bank Rate at 3.75% (held; next MPC 17 September 2026), statutory interest is 11.75% where the Late Payment of Commercial Debts rules apply. Soften: consumer householder contracts are different - do not paste commercial statutory interest onto every domestic invoice without checking your terms and the consumer regime. Put clear due dates on every invoice. See late payment rights.
Step | Practical action |
|---|---|
1 | Send a polite reminder with the invoice number and due date |
2 | Call or WhatsApp the accounts contact; note the date |
3 | For commercial debts, consider a formal late-payment notice before interest / compensation claims |
4 | Keep chasing proportionate - do not invent penalties your terms do not allow |
How InvoiceAdept fits a cavity wall insulation installer
InvoiceAdept is built for UK trades invoicing - including insulation and fabric packages - not for filing tax returns.
Plan | Price (excl VAT) | What you get for cavity jobs |
|---|---|---|
Free | £0 | Five invoices per month - enough to trial householder jobs |
Pro | £7.99 | Unlimited invoicing pattern for growing installers; WhatsApp send |
Pro+ | £12.99 | CIS labour/materials lines for contractor packages |
Stripe processes card links (UK cards typically 1.5%+20p). InvoiceAdept adds no platform fee on top of Stripe. InvoiceAdept does not file CIS300, VAT returns, Making Tax Digital updates or Self Assessment. It does not issue Building Control certificates, ECO4 / GBIS forms, TrustMark evidence, CIGA certificates or ventilation certificates.
Soft CTA: raise your next cavity fill invoice with the InvoiceAdept invoice generator - Free five invoices, Pro at £7.99, Pro+ at £12.99 (excl VAT).
Quote versus invoice on cavity wall packages
A quote is the offer. An invoice is the request for payment for work done or a deposit due. Do not send a quote PDF labelled as an invoice when you want payment - accounts teams and householders need an invoice number, a due date and a tax point.
Document | Purpose | Typical timing |
|---|---|---|
Quote / estimate | Scope, product, elevations, make-good, price, terms | Before acceptance |
Deposit invoice | Collect money before ordering materials | After acceptance, before order |
Stage invoice | Survey or drill/fill milestone | When the stage trigger is met |
Final / completion invoice | Balance, variations, deposit credits, snag close | Practical completion / handover |
Retention release invoice | Release retained slice after the defects period | On the diary date in the contract |
Credit note | Correct overbilling or unused deposit | When the adjustment is agreed |
Building Control, guarantees and certificates - the invoice is not a certificate
Cavity fill may sit beside Building Regulations, competent-person schemes, manufacturer warranties and guarantee-agency paperwork. Soften absolute claims. Your invoice can narrate that a guarantee application was submitted or that a certificate number will follow - but the PDF itself is still only a request for payment.
Document | What it is | What your invoice is not |
|---|---|---|
Invoice | Request for payment with scope and amounts | Not Building Control completion |
Guarantee / CIGA-type certificate | Scheme paperwork if you are enrolled and the job qualifies | Not something InvoiceAdept issues |
ECO4 / GBIS evidence | Scheme measure paperwork | Not invented £ amounts on the invoice |
Damp / ventilation report | Specialist survey if separately commissioned | Not your cavity fill invoice |
Variations that commonly appear on cavity wall jobs
Variation | Invoice tip |
|---|---|
Extra elevation discovered after survey | Code V01; written approval; separate line |
Extraction of failed historic fill | Separate stage or variation - do not bury in "survey" |
Internal plaster patch after blow-through | Clear making-good line; or pass to plasterer guide |
Scaffold days extended | Access variation with hire ticket reference |
Airbrick / vent replacements beyond quote | Count and product on the variation line |
Client-requested delay / remobilisation | Only if your terms allow a remobilisation charge |
Keep variations out of a silent "additional wall works" blob. Written approval first; invoice second.
Retention, credit notes and variation orders
On contractor packages, retention is common. Show it clearly:
Gross value of the stage or package
Retention percentage and amount withheld
Net due now
Retention release date from the contract
A separate retention release invoice later
Credit notes correct overbilling, unused deposits or cancelled elevations. Do not "fix" an issued invoice by editing history - issue a credit note and, if needed, a replacement invoice. See calculate retention payments.
Item | Deposit | Retention |
|---|---|---|
When money moves | Before / during works (to you) | After completion (held by client) |
On the invoice | Deposit invoice then credit on finals | Show withheld; invoice release later |
VAT tax point | Often on receipt of deposit if registered | Follow your VAT treatment of the underlying supply |
CIS | Only if contractor-paid and CIS applies to that payment | Same - retention release can still be CIS-relevant |
How to describe cavity wall insulation without sounding like a brochure
Prefer plain, checkable words:
"Bonded polystyrene bead cavity fill to front, rear and both side elevations at 12 Example Road"
"Mineral wool blown cavity insulation; drill, fill and make-good; airbricks left clear"
"Named foam system as per quote Q-441; make-good mortar colour matched to existing"
"Extraction of failed historic fill to rear elevation; waste removed; re-fill as stage 2"
Avoid brochure fog: "eco thermal upgrade package", "premium comfort walls", "whole-home energy transformation" without product, elevations or stage.
Snagging and practical completion on cavity fills
Practical completion for a cavity fill package usually means elevations in scope are filled, holes made good, site cleaned, and agreed snags closed - not that a guarantee certificate has already arrived in the post. Soften. Diary the guarantee / certificate paperwork separately from the payment due date unless your contract makes payment conditional on a specific document.
Snag example | Invoice handling |
|---|---|
Missed make-good hole | Close before final; or withhold a small agreed snag sum |
Mortar colour mismatch | Remake; do not invent a free full re-point |
Blocked airbrick found at handover | Clear / replace as agreed; variation if out of scope |
Client adds fifth elevation after fill | New variation - not a free snag |
Sample line-item pricing tables (examples only)
All figures below are illustrative examples for paperwork training - not UK market rates, not a survey and not a price list.
Example line (householder bead package) | Illustrative amount |
|---|---|
Survey and suitability check | £120 |
Drill and bonded bead fill - front and rear elevations | £980 |
Drill and bonded bead fill - two side elevations | £640 |
Make-good and re-point drill holes | £180 |
Waste and clean-down | £70 |
Example line (contractor multi-plot) | Illustrative amount (ex VAT) |
|---|---|
Labour - Plots 7-9 cavity fill and make-good | £2,700 |
Materials at direct cost - beads and mortar | £1,900 |
Access / tower hire ticket (if recharged) | £220 |
Variation V01 - additional gable elevation Plot 8 | £410 |
Example deposit maths | Illustrative |
|---|---|
Quoted package | £2,000 |
Deposit 25% before materials order | £500 |
Stage after drill/fill | £1,000 (credit deposit on final) |
Final after make-good | £500 balance |
Pricing comparison: Free / Pro / Pro+ for insulation firms
Need | Free (£0) | Pro (£7.99 excl VAT) | Pro+ (£12.99 excl VAT) |
|---|---|---|---|
Five householder invoices / month | Yes | Yes (unlimited pattern) | Yes |
WhatsApp send | - | Yes | Yes |
CIS labour / materials lines | - | - | Yes |
Card links via Stripe | Stripe fees apply | Stripe fees apply | Stripe fees apply |
Files CIS300 for you | No | No | No |
Checklist before you hit send
Legal name matches the bank account and (if Ltd) Companies House
Unique invoice number and clear due date
Site address, product family, elevations in scope, stage named
Airbrick / flue narrative if you agreed to check them
Labour / materials split when CIS applies
Deposit credits and retention maths shown clearly
VAT: 0% only with Notice 708/6 narrative when conditions met; never invent commercial 0%; do not stretch onto decorative-only render
No CIS block on private householder invoices
No fake ECO4 / GBIS £ amounts
Invoice is not sold as a CIGA or Building Control certificate
VAT threshold wording uses £90,000 if you mention it
FAQ
What should a UK cavity wall insulation invoice include?
Legal names and addresses, a unique number, dates, a description that names the site address, product type (beads, mineral wool, named foam), elevations or coverage, drill/make-good, stage, quantities and rates, a due date and a way to pay. Split labour and materials on contractor jobs. VAT only if registered - including 0% with Notice 708/6 narrative when that genuinely applies. UTR and CIS only under a contractor, and only when CIS actually applies.
Do cavity wall insulation installers need a CIS invoice?
Only when a contractor is paying you for construction operations that are in scope. Lead with CISR14240 for fitting thermal insulation as part of a wider construction project. A homeowner job you sold yourself: no CIS. Soften where premises are not undergoing construction and the work has no fabric effect - though drill-and-fill typically does affect fabric.
How do CIS deductions work on beads, wool and foam?
When CIS applies, deduction usually sits on labour. Materials you bought at direct cost are typically excluded from the deduction base - CISR15060 / CISR15090. Keep tickets. Do not list free-issue materials as yours. Common rates are 20% verified and 30% unverified - check live HMRC status for that subcontractor.
Do I charge 0% VAT on every cavity wall insulation job?
No. Qualifying residential (and relevant charitable) installs of energy-saving materials including wall insulation can be zero-rated under Notice 708/6 from 1 May 2023 to 31 March 2027 when conditions are met. Supply without install is usually standard-rated. Commercial installs outside scope should not be forced to 0%. Decorative render is not automatically the same relief. InvoiceAdept does not decide VAT status.
Is cavity wall insulation the same VAT treatment as external render?
Not automatically. Notice 708/6 focuses on installation of specified energy-saving materials such as insulation for walls. A decorative or weathering render package is a different supply - test it separately and prefer cautious wording over overclaiming zero or reduced rates.
Should I take a deposit before ordering cavity fill materials?
If your terms require it, yes - before you order large volumes of beads, wool or foam. Raise a numbered deposit invoice and credit it on later stages. See the deposit invoice template.
How should I invoice bead fill versus mineral wool or foam?
Use separate clear lines: product family, elevations, method (inject / blow), make-good. Do not merge them into a single "cavity insulation" blob when the quote priced them differently.
Does InvoiceAdept file CIS, VAT or Making Tax Digital to HMRC?
No. It raises the invoice, stores the record and on Pro+ prints CIS lines. It does not file CIS300, VAT returns or MTD quarterly updates. It does not issue Building Control certificates, ECO4 / GBIS forms or CIGA certificates.
What is the VAT registration threshold?
£90,000. Not £85,000.
What is the deemed CIS contractor construction-spend test?
More than £3 million on construction in the 12 months since the first payment for non-construction businesses - not £1 million. Mainstream construction contractors register when they pay subcontractors for construction work.
Can I reverse-charge a householder for cavity wall insulation?
No. And reverse charge does not apply to zero-rated Notice 708/6 supplies either.
What payment terms should I use?
A practical residential default is 14 days from invoice date with a calendar due date. Commercial jobs follow the PO or contract. Put terms on the quote and the invoice. See how to invoice a client.
Can I put ECO4 or GBIS grant amounts on the invoice?
Only if a specific grant or scheme contribution is a factual part of how that job is paid, and even then keep invented market-wide grant figures off the page. Check live scheme rules when you need numbers. The invoice is still not the grant form.
What if the main contractor free-issues the insulation materials?
Invoice labour (and any materials you actually bought). Do not list free-issue beads or bags as your materials for CIS.
Sole trader or limited company - does the template change?
Yes for the name block (personal name vs registered company name and number). CIS and VAT rules still follow the facts of the job and registration, not the template title.
Are make-good and re-point lines zero-rated?
Soften. Genuinely ancillary making-good that forms part of a qualifying energy-saving materials install may follow the principal supply when Notice 708/6 conditions are met - but do not stretch every facade re-point or decorative mortar job into zero-rating. Test facts; InvoiceAdept does not decide.
Pro versus Free - which plan for insulation subcontractors?
Free is £0 for five invoices per month - useful for a small householder pipeline. Pro at £7.99 excl VAT suits growing volume and WhatsApp send. Pro+ at £12.99 excl VAT adds CIS lines for contractor packages. Stripe UK cards 1.5%+20p still apply on card links.
Related guides
About this guide
Written for UK cavity wall insulation installers and subcontractors who need readable invoices for householders and contractors. Rules and HMRC links checked 9 September 2026. General information only - not tax, legal, Building Regulations, grant, damp diagnosis, ventilation design or install certification advice. InvoiceAdept does not decide CIS or VAT status and does not file returns to HMRC. InvoiceAdept is from Tech Me Today Ltd, Companies House 15917255, ICO ZB944663. Free five invoices / Pro £7.99 / Pro+ £12.99 (excl VAT).
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