CADSnap · QS + contractor decision cockpit

Know what the contract owes you. Before the lawyer letter.

Free decision tools for UK QS, main contractors, sub-contractors and construction consultants. Retention release. Payment notice + pay-less deadlines. Adjudication math. Bond + PCG modelling. HGCRA 1996 + LDEDC 2009 aware. All before you escalate.

Run the retention calc → All calculators
5
Calculators
8%
+BoE base on late pay
£0
To find out
60s
Per answer
Hero calculator · /calc/retention-release

When does the retention release? And what's the interest if it's late?

Five fields. The first and second moiety release dates, statutory late-payment interest under the Late Payment of Commercial Debts Regulations, and the cash position right now.

Total value of the works under the contract.
JCT default 3%. Some bespoke contracts 5%.
First moiety (half) typically releases at PC.
JCT default 12 months. Sometimes 6 or 24.
Days past the contractual due date for the release.

CADSnap is decision support · not construction law advice · operator stays accountable

The other four

Four more answers before you escalate.

/calc/payment-notice

Payment + pay-less notice deadlines

Section 110A + 111 HGCRA 1996. Due date, final date for payment, last day to serve a valid pay-less notice. Miss it and you owe the notified sum.

/calc/adjudication-fee

Adjudication fee + likely outcome

Estimated adjudicator fee, claimant costs, response window. Whether a 28-day adjudication is worth the noise versus a TCC claim.

/calc/bond-pcg

Performance bond + PCG modeller

Bond cost vs Parent Company Guarantee. Premium estimate, security ratio, what an employer is actually trying to protect.

/calc/cad-to-dxf

Sketch / drawing → CAD conversion

Drop a sketch or PDF — get a clean DXF + bill-of-quantities estimate. The pre-tender takeoff before you commit a QS day.

All four are wired with the same lead-capture pattern — drop your email after any result.

Also useful

Once the contract is paying right…

CADSnap covers the contract. These cover the people, the materials and the exit.

How CADSnap stays current

Built against the Construction Act. Refreshed weekly.

HGCRA 1996 + LDEDC 2009
Sections 110, 110A, 111 — payment notice + pay-less rules apply to all construction contracts
Scheme for Construction Contracts
Default adjudication procedure when the contract is silent or non-compliant
Late Payment of Commercial Debts
BoE base + 8% statutory interest on overdue commercial debts (incl. retention)
JCT + NEC standard forms
Retention defaults, defects liability periods, payment cycles modelled against current 2024 editions

FAQ

Is CADSnap construction law advice?
No. CADSnap is decision support — the pre-claim numbers and timing before the lawyer is involved. For a regulated opinion talk to a construction solicitor or CIArb adjudicator. We point you in the right direction; we don't replace them.
What's a moiety?
It's half the retention. JCT (and most bespoke) contracts release retention in two equal halves: the first moiety at practical completion, the second moiety at the end of the defects liability period (often 12 months later). The calc shows both release dates.
What interest rate applies if retention is paid late?
Under the Late Payment of Commercial Debts (Interest) Act 1998 (as amended), statutory interest is the Bank of England base rate + 8% per annum on the unpaid sum, plus a fixed compensation amount per invoice. The calc applies this against your days-overdue input.
Does this work for sub-contractors too?
Yes. The retention release rules apply down the chain — main contractor to sub, sub to sub-sub. The same calc works whether you're the QS chasing the employer or the trade chasing the main.
Where does my email + result go?
Your result is sent to your inbox. Your details land in the BRG intelligence layer (Supabase, RLS-protected) so we can follow up with a sector plan. We never share or sell your data. Consent is explicit and tied to the marketing opt-in box.
Decision support, not construction law advice. Operator stays accountable.