Fitting windows and glazing is alteration of a building, so it is inside CIS. Installing blinds and shutters is excluded by name. The same fitter, on the same job, can cross the line in an afternoon.
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Find out moreFitting windows, doors, curtain walling and glazing is alteration of a building or structure, so it is a construction operation and inside CIS. Section 74(3) then excludes two things that land squarely in this trade: the installation of seating, blinds and shutters, and the manufacture of building components and their delivery to site.
So a window installation is inside the scheme. Fitting the blinds afterwards is not. And manufacturing sealed units in your own factory and delivering them for somebody else to fit is outside it too.
That is three treatments available to one business — and because the domestic reverse charge takes its scope from the CIS definition, each one also carries its own VAT answer. A blended invoice covering windows and blinds is a figure nobody can justify afterwards.
Glazing in the course of constructing a new dwelling, before completion, can be zero-rated. Replacement windows in an existing occupied dwelling are repair or alteration and are standard rated at 20% — including in an extension. Insulation and draught stripping are qualifying energy-saving materials, zero-rated until 31 March 2027 and 5% from 1 April 2027, but double glazing as such is not on the qualifying list.
The deduction is charged on the payment less materials you directly incurred, consumable stores, fuel other than fuel for travelling, plant hire, the cost of manufacture or prefabrication, and the VAT you charged. Travel and subsistence stay in. And where the contractor buys the materials and recharges them, you have not directly incurred them, so no reduction is due at all.
If the deduction is costing you cash, gross payment status removes it. The turnover test is £30,000 of relevant payments net of VAT and materials for a sole trader. The compliance test, which since 6 April 2024 includes VAT, is the part that needs preparing for.
If you are paid under CIS, the deductions taken during the year are set against your tax bill and any excess is repaid. The CIS refund estimator gives a rough figure, how much is a CIS tax refund covers what decides it, and what you can claim lists the costs that count. Earlier years can still be claimed within the time limits, and a limited company recovers its deductions through the payroll instead. Keep every payment and deduction statement, because they are the evidence for the claim.
If you are VAT registered, the domestic reverse charge decides whether you charge VAT to a main contractor, and the reverse charge checker works through a single invoice. It also changes whether the Flat Rate Scheme is worth keeping.
Our fees are a fixed monthly amount agreed before we start, with payroll and CIS returns priced separately. For the books, FreeAgent is included with an eligible Mettle business account: see bookkeeping software for trades.
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Section 74(3) excludes the installation of seating, blinds and shutters. That is the statutory wording. A business that treats a shutter installation as CIS work has both the deduction and the VAT treatment wrong on the same invoice. Treating CIS work as a shutter installation gets both wrong too. Section 74(3) also excludes signwriting and the erection of signboards and advertisements, which is the neighbouring trap for anyone fitting shopfronts.
Fitting is alteration of a building and is inside CIS. For VAT it is standard rated at 20%, because work on an existing occupied dwelling is repair, maintenance or alteration. Where the work is in the course of constructing a new dwelling, before completion, the zero rate can apply instead — and zero-rated supplies are outside the reverse charge entirely. The stage of the building decides it: the test is whether the work is in the course of construction and before completion.
Either way it comes out of the payment subject to deduction — materials you directly incurred are excluded, and so is the cost of manufacture or prefabrication. What matters is that it is identified. An invoice showing one figure for supply and fit gives the contractor nothing to exclude, and the contractor is the one who has to justify the materials figure. Where the figure is withheld or looks inflated HMRC expects the contractor to estimate it, so a line reading “supply and fit glazing” invites an estimate while “units £2,400, fit £900” does not.
Sometimes. Insulation and draught stripping are qualifying energy-saving materials, so installing them in residential accommodation is zero-rated until 31 March 2027 and 5% from 1 April 2027. Double glazing as such is not on the qualifying list. And the relief only applies where the materials are installed — supply-only is standard rated. So a glazier fitting insulated units alongside insulation and draught stripping may have two rates running on one job until 31 March 2027, and two different rates again from 1 April 2027.
We act for trade businesses everywhere in the UK and work with you remotely, so your postcode does not decide whether we can help. Your CIS and VAT position does not change when you cross a border either — but the building safety rules and the levy do, which is what the area pages cover.
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