Refurbishment and renovation calculator
This refurbishment and renovation calculator will estimate the loan, interest and total cost of buying and improving a property from your own figures. The calculator is coming soon; the guide below explains each input.
Reviewed by David Sampson, Founder & Director · Created 20 October 2026 · Last reviewed 20 October 2026
What will the refurbishment calculator show?
A refurbishment calculator estimates the loan, the interest and the total cost of buying a property that needs work and carrying out the works. Enter the purchase price, the works budget, the deposit, the rate and how long the project will take, then the expected value once the works are done, to see the margin left at the end.
Every figure will be an input, so the result reflects the numbers entered rather than market data. It is a planning estimate, not a quote or a lending decision. How refurbishment lending works is explained in the refurbishment finance section.
The inputs explained
The loan covers part of the purchase price and, where the lender funds them, part of the works. The rate should come from a quote, and the term is the number of months the project is expected to take. Interest on short-term finance is often rolled up or retained, so it is added to the loan rather than paid monthly.
The finished value is the estimated value once the works are done, which a lender's valuer will confirm. Lenders use their own valuation, so their figures may differ from those entered.
Fees for arrangement, exit, valuation and monitoring can be entered separately. Pricing across refurbishment lending is explained on the refurbishment finance rates page.
Using the result
The result helps set a budget and test a project before speaking to a lender. Testing a longer programme, a higher works cost or a lower finished value shows how sensitive the margin is to change. Stamp duty, legal fees and the cost of the mortgage that replaces short-term finance are not included and need adding.
Until the calculator is live, the same sums can be worked out by hand. Monthly interest is the loan multiplied by the monthly rate, and the margin is the finished value less the price, works, interest and fees. A broker can quote current pricing for a specific case.
Frequently asked questions
How do I calculate refurbishment finance costs?
Add the interest over the project, the fees and the works to the purchase price, then compare with the finished value.
Is the refurbishment calculator live?
Not yet. The calculator is coming soon. The guide on this page explains how each input works.
Does it work for a renovation mortgage?
Yes. Enter the price, the works budget and the finished value.
What is rolled-up interest?
Interest added to the loan each month and paid when the loan is repaid.
Does the result include stamp duty?
No. Stamp duty and legal fees are extra costs to add.
Is the result a loan offer?
No. It is an estimate from the figures entered. Only a lender can make an offer.
Important: Your home may be repossessed if you do not keep up repayments on your mortgage. Information on this page is for general guidance only and does not constitute financial advice.Always verify details directly and seek independent advice before making financial decisions.