House Renovation Cost Calculator

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Many of our new readers join us by searching for a house renovation cost calculator. Over the past 14 years we have collected real cost data from our projects and are happy to share the figures with you.  Below you will find links to the cost of major home renovations as well as to cost of home electrics, cost of flooring, cost of decoration and so on.

pricing spreadsheet to calculate building costs

Before directing you to specific values, we want to point out that these costs are founded on strong design and project management principles, which you should also take time to read. Our costs are well-controlled, and this doesn’t happen by accident. So, before we set you loose on the data, we spend some time explaining how we control cost, and lead you to our guides for successful property renovation.

house renovation cost calculator

House renovation costs

It is tempting to dive straight into the cost figures and forget to read the supporting guidance that we offer. That’s perfectly fine if you just want some ballpark budgetary information to get you started. But it is important to understand how the costs were derived, agreed and managed. In 14 years we have never had a project go over-budget and there is a reason for that; the care and attention we take in designing, specifying, planning, contracting, controlling and monitoring; you should do the same. You can read separately about our interior design and house renovation services which underpin this.

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house renovation design and specification

The key to keeping costs under control is to spend sufficient time up front finalising the design and specifying the requirement clearly. Drawings are only part of the story; you also need a written document to address the remainder: specific floor and paint finishes, underfloor heating, kitchen cabinets and appliances, bathroom suite, special lighting and so on. The total package is therefore a set of drawings accompanied by a written specification covering all the contractor’s work, and a separate document listing the additional supply items (kitchen, floor, bathroom suite and so on). This then defines the totality of the spend. You can read more about this in our piece entitled Controlling the cost of house renovation.

Brexit and Interior Design

You should also obtain all the necessary approvals to avoid unwanted surprises and costs later. We manage planning applications and engage structural engineers and others for building control and construction drawings. We also manage Party Wall agreements where required. You may also need a no objections letter from the water authority; in a recent project we had to show that proposed works were more than 3m away from public sewer that ran across our client’s garden.

Planning applications Bath and BANES

Contracting for house renovation

For more extensive and expensive renovations we hold a competitive tender for our clients, taking time to visit contractor’s previous work, obtain references and clarify responses. We’ve written separately on choosing and working with contractors.

During a recent tender we used our experience to drive down prices, obtaining 15-20 % savings for our clients (exceeding £17000). This, in itself, more than paid for our project management fee! This underlines the importance of engaging the right specialists at the right time; they can save you a considerable sum.

Having agreed a fixed price, the next step is to enshrine this in a formal contract. We usually use an off-the-shelf JCT minor works contract. This then binds the contractor to deliver the detailed specification for the agreed price.

Renovating the house

Then the work begins. Because you have taken the trouble to specify all the detailed requirements in your specification, there will be little wriggle room for price increases. There may be some elements that were reasonably expressed as prime cost sums (PC sums) or provisional sums, because of a lack of information at the time (awaiting the result of exploratory work is a good example). However, these prices will be fixed once the additional information becomes available. A good client will have set aside a sensible risk provision for this (commonly referred to as a contingency), so there should still be no big surprise.

By monitoring progress and quality effectively, you will achieve your renovation for the stated price. You can read more on how to achieve success in our property renovation guide.

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House renovation cost calculator

This is the bit you’ve probably been waiting for, but please remember to read the accompanying details for successful house renovation;  your final costs will depend upon it! The figures in the links below are for guidance only, but should give you a reasonable budgetary estimate to get you started.

We derived the figures from renovations carried out in the Bath-Bristol area, which is moderately affluent, but you will need to apply some adjustment for other regions. Typically, you can add 5-10% for projects in London and the South East; for the rest of the UK, you may find prices around 5% lower on average.

To use data from older projects, we uplifted their values to January 2016 economic conditions; this assumed an average annual inflation rate of 3.5%. However, with uncertainty surrounding Brexit and the reduction in the value of Sterling, prices since the referendum have risen by approximately 15-20% per annum on some construction and supply costs. You will need to take this into account when estimating values at current economic conditions, until more certainty returns.

We hope you find this informative. We’ve carried out many house renovations over the years. If you feel that we can help with your renovation, please get in touch on 07711 857670 or use the contact form on this website.

Best wishes for a successful project.

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