Manufacturing components in your workshop is outside CIS. Fixing them into a building is inside it.
Off-site manufacture of building components, and delivery of them to site, are not construction operations. Installation is. So a joinery firm that makes in its own workshop and fits on site is sitting on both sides of the scheme, often on the same job.
HMRC’s guidance at CISR14150 puts fitted kitchens, fitted bathrooms, cupboards and shopfitting inside CIS where the work is part of the construction, alteration, extension or repair of a building. Fixed seating is the odd one out. It is excluded by statute, and so is the installation of blinds and shutters.
Where the workshop line gets complicated
Splitting the invoice is the obvious answer, and on its own it is not enough.
Where one contract covers both the manufacture and the installation, the mixed contract rule can pull all the payments under that contract into the scheme, including the workshop element. Two lines on an invoice do not undo that. What matters is how the work is contracted in the first place, and whether the manufacture and the fitting are genuinely separate supplies or one job with two lines on the paperwork.
The other half of it is the deduction itself. CIS deductions come off the labour element after the cost of materials is taken out, so the materials in a manufactured item need to be identified on the invoice. A joinery firm that bills “supply and fit, £18,000” with no breakdown is inviting a contractor to deduct 20% from the whole lot, workshop timber included.
That money comes back eventually. In the meantime it is sitting with HMRC instead of paying your wage bill.
Workshop plant and capital allowances
A joinery workshop carries far more capital equipment than most trades of the same size. Spindle moulders, panel saws, CNC routers, extraction, compressors, racking and the building itself.
Annual Investment Allowance covers most of it. For a limited company buying new plant, full expensing may be the better route. Which one you use, and what year you buy in, changes your corporation tax bill more than most joiners realise.
Second-hand kit bought at auction counts too, and it is the thing that most often never makes it onto the fixed asset register at all.
Timber stock and work in progress
Your year end figures depend on two numbers that are easy to get wrong.
Stock, meaning the timber, sheet material, ironmongery and finished units sitting in the workshop on the last day of the year.
Work in progress, meaning the jobs that are part made and part fitted, where you have spent money and not yet invoiced. Under-record it and you understate your profit and your balance sheet. Over-record it and you pay tax on work you have not been paid for.
For a firm running several one-off contracts at different stages, this is not a year end tidy-up job. It needs a system that tracks it all year.
Pricing made-to-measure work against true cost
Most joinery quotes are built on materials plus an allowance for time. The materials are accurate. The time rarely is.
Setting out, machining, sanding, finishing, snagging and the second trip back to site are all real hours, and they are the ones that get lost between the workshop and the job sheet. A firm can be busy all year on one-off work and make less than it does on repeat runs it barely thinks about.
Job costing that splits workshop hours from site hours tells you which of your work is actually worth taking.
What we do
CIS applied properly across workshop and site work, with the contracting and invoicing set up so the treatment follows the work.
Capital allowances claimed in full on workshop plant, including the kit that never reached the asset register.
Stock and work in progress valued on a system rather than guessed at the year end.
Job costing that separates manufacture from installation, so you can see the margin on each.
The routine compliance runs alongside all of that. Accounts, corporation tax, VAT, payroll and self assessment.
Who we work with
UK joinery and shopfitting limited companies turning over between £500,000 and £5 million, anywhere in the country.
Common questions
Is joinery inside CIS?
Site installation is, where it is part of the construction, alteration, extension or repair of a building. Manufacturing components in your own workshop is not.
Are fitted kitchens inside CIS?
Yes, where they are installed as part of construction, alteration, extension or repair work. HMRC lists fitted kitchens, bathrooms, cupboards and shopfitting.
Is fixed seating inside CIS?
No. Installing seating is specifically excluded by statute, along with blinds and shutters.
Can I split my invoice between workshop and site to keep the workshop element out of CIS?
Not by itself. Where one contract covers both, the mixed contract rule can bring the whole payment into the scheme. The answer is usually in how the work is contracted.
Should materials be shown separately on my invoices?
Yes. CIS is deducted from the labour element after materials are taken off, so a lump sum invoice with no breakdown costs you cash.
Book a call. Send us a recent supply and fit invoice and we will tell you what a contractor is entitled to deduct from it and what they are not.
Common questions
Does CIS apply to joiners?
Manufacturing components in your workshop is outside CIS. Fixing them into a building is inside it. Off-site manufacture of building components, and delivery of them to site, are not construction operations. Installation is. So a joinery firm that makes in its own workshop and fits on site is sitting on both sides of the scheme, often on the same job.
Does the VAT domestic reverse charge apply to joiners?
Usually yes. The domestic reverse charge follows CIS scope. Where you supply joiners work that falls inside CIS to a customer who is VAT registered, registered under CIS and is not an end user, you do not charge VAT on the invoice. Your customer accounts for it instead. Supplies to homeowners and to end users stay outside it, and you charge VAT the normal way.