Extension Compliance Currently booking July

Extension SAP, sorted fast.

The Part L SAP calculation your extension needs for Building Control — produced fast, priced up front.

Extension Compliance — example UK residential project

Larger or heavily-glazed extensions have to prove Part L compliance, usually through a SAP calculation that shows the extension does not worsen the dwelling’s energy performance. We produce the calculation your Building Control Officer will ask for, priced up front with no hidden or extra fees, with unlimited specification revisions if the design changes.

Fixed price in writing
Produced to fit your programme
Before you ask
Not sure you need all of these?

Send your drawings. We review them free of charge and quote only what your project actually needs. Nothing more.

How fast can you turn it around?

Most calculations are produced within a few working days of receiving your drawings. Working to a deadline? Tell us and we will prioritise your project.

Project a bit different?

Conversions, extensions, mixed and commercial schemes are all handled. One call on 01455 242297 confirms which package fits, in about five minutes.

377+ five-star reviews
“Absolutely amazing service. We urgently needed a SAP assessment and it was sorted within a week — a seamless, hassle-free service.”
Lisa Hickman Verified review
Currently booking July. Fast turnaround.
Here's what you get
  • Design Stage + As Built SAP + EPC
    From £75
Plus these, included as standard
  • + Unlimited SAP specification revisions
    Included
  • + Free Dashpivot collaboration app
    Included
  • + Pre-quote drawings review
    Included
From £75 + VAT

We confirm your full fixed price within 48 hours of seeing your drawings.

Fixed price Accredited assessors
Get my package quote 01455 242297. Speak to a human
Quote within 48 hours
Fast turnaround
What's in the package

One service.
Done properly.

The Part L energy compliance an extension needs for Building Control — the SAP calculation (and EPC where a new dwelling is created).

Produced and lodged by accredited assessors, priced up front with no hidden or extra fees.

01 Part L
£75
+ VAT

SAP Calculation

Design Stage plus As Built SAP plus the final EPC. Proves your Dwelling Emissions Rate meets the Target. The headline Part L compliance check.

  • Design Stage SAP for Building Control
  • As Built SAP and EPC at handover
  • Unlimited specification revisions
About this service
Included as standard

What you can count on.

Set out in writing before you book — clear value up front, with no hidden or extra fees.

1
Fixed price, in writing

The number we quote is the number you pay

Every package is priced up front in writing. No mid-project surprises, no added line items, no hidden or extra fees. If scope genuinely needs to grow, we ask before we do a thing.

2
Built around your programme

Produced to fit your build programme

Calculations are typically with you within a few working days of drawings arriving. Working to a tight deadline? Tell us and we will prioritise your project.

3
Accredited assessors

Produced by accredited assessors

Every calculation and certificate is produced and lodged by accredited assessors, so it is valid and accepted by Building Control.

How it works

From drawings to
sign-off.

1

Send details

Send your drawings and specification. We confirm a fixed price within 48 hours.

2

We produce it

Your calculation is produced by an accredited assessor, typically within a few working days.

3

Issued for sign-off

We issue the completed report and lodge any certificate, ready for Building Control sign off.

Results, not sales copy

Real builds.
Real reviews.

Verified reviews from clients across the UK — the kind of work this package is built on.

Speed
“Excellent service! The team were knowledgeable, efficient and easy to work with. Our air tightness test was booked quickly and the results came through the same day. Would highly recommend.”
CT
Chris Tanner
Verified review
Value
“Exceptional service at a fair price! Quick efficient communication, understood exactly what I needed to satisfy local building control and then made the process easy. I didn't have to chase them, was very clear about timescales and delivered ahead of time.”
RB
Rich B
Verified review
Whole build
“First class service from start to finish. Over the course of my two year build UK Building Compliance were always prompt with their response and made the whole process very smooth.”
LB
Laurence Buck
Verified review
10,000+
Tests completed
15+
Years experience
377+
Five-star reviews
UK
Nationwide coverage
Questions we get on this package

Before you ask us.

Does my extension actually need a SAP calculation?

It depends on the extension. Building Control may accept compliance through limiting the glazed area or improving elements elsewhere, but larger or heavily-glazed extensions usually need a SAP calculation to demonstrate Part L compliance. Send your drawings and we will confirm what applies — at no charge.

How fast is it?

Most extension SAPs are produced within a few working days of receiving your plans and specification. If you are working to a deadline, tell us and we will prioritise your project.

What if the design changes?

Specification revisions are unlimited — change your glazing, fabric or heating and we re-run the calculation, no fee per revision.

Can you do this anywhere in the UK?

Yes. We cover England, Wales, Scotland and Northern Ireland, with the equivalent energy standards handled under the same price.

Currently booking July

Send your drawings today.
From £75 + VAT, fully managed.

Fixed quote back within 48 hours. Nothing added after signature — no hidden or extra fees, everything set out in writing.

Fixed price Accredited assessors
“We use UKBC for all our SAP calculations and EPC ratings. Always reliable, always on time, and the team genuinely understand what builders need. Top marks.” Martin Reid, Verified review
What you get
  • SAP + EPC Fixed price
  • Revisions, re-tests & diagnostics Included
From £75 + VAT
Get my package quote 01455 242297. Speak to a human

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