modern-grey-kitchen

Controlling the cost of house renovation

You may be thinking of doing up your home, but how do you control the cost? If you are planning a refurbishment, this article offers tips and advice for making sure your dreams remain affordable.

knowing the cost of house renovation is important for our clients

“We’ve gone over budget”

Words often heard on TV property shows.  The two main reasons for this are:

  • the owners didn’t start out with a realistic figure for the main features of the project, and
  • they didn’t appreciate all the other costs that accompany a renovation.

I can put my hand on my heart and say that we have never had a project go “over budget”. There are four key ingredients for controlling cost:  a taut specification, a fixed price, an appropriate payment schedule, and understanding the totality of the task (and hence the total cost). We spend an age on the first, tie down prices for the second, agree suitable payments for the third, and detail everything for the fourth. You can do the same.

You’ll find links at the foot of this blog to advise you further on successful house renovation, as well as a guide on what things cost.

detailed contractor's specification

Home renovation specification

A key factor in controlling the cost is a taut specification.  This pre-supposes the following:

  • you are clear on your requirement and won’t make significant changes part-way through.
  • you have detailed construction drawings for projects with structural changes.
  • you have produced a floorplan to scale and identified electrical, lighting and heating requirements.
  • you have scale kitchen and bathroom designs.
  • you have a good idea of finishes, fixtures and fittings.
  • you are clear on what a contractor is to supply and what you will supply.
  • you have written down what the contractor is to do
  • you have written down what else needs to be done by others.
  • you have done your homework and have a realistic expectation of what things cost, and how long they take.

 

kitchen fitters marking out for wall units

It helps to separate the specification into the contractor’s five main trade annexes:

  • structural and building;
  • plumbing and heating;
  • carpentry and joinery;
  • electrical; and
  • decoration.

We also reserve an extra annex for “other” which may include works to the garden or patio. We and our contractors find this easier than a room-by-room separation, particularly for larger projects.  Each annex effectively forms a package of work to be handed to a specific trade, which may be a sub-contractor.

Each requirement, or group of requirements, in your specification should be priced. This populates the first section of your pricing spreadsheet.

pricing spreadsheet to calculate building costs

Pricing spreadsheet

Our pricing spreadsheets have 4 sections.

  • price for contractor’s work (labour and materials)
  • price for furnishings and fittings (those not supplied by the contractor, including any external labour, like hanging curtains)
  • professional fees
  • risk provision.

 

striped winding stairs

Estimates and quotations

You may know that an “estimate” is just that – an estimate; it is not binding. Price increases can result if an estimate is re-evaluated upwards when the final bill is delivered. Always ask for a fixed price “quotation”.

For higher value projects, a competitive tender should help you to obtain better value for money. When choosing your contractor, make sure you are comparing like with like. The more detailed your specification, the more likely you are to obtain a true price comparison.

For more complex renovations, fix the prices that can be fixed. However, there may be other elements which are not yet fully defined. Here, it is reasonable for the contractor to include a “provisional sum” (PS) or “PC Sum” (PC), which are reasonable judgments on the eventual price of those elements when they arrive. PS and PC can lead to price increases so it is best to minimise these as far as possible before placing the contract. We explore this further below.

House renovation contracts

You can write a contract for most simple house renovations yourself, using your written specification and a covering letter with agreed prices, signed up to by all parties. For more significant projects, particularly those involving structural work, you should use a standard document such as the JCT Minor Works contract. They are available to purchase on-line and cover everything you need – just fill in the gaps (name, price etc).

chimney breast removed exposing ceiling void

Paying the contractor

Your contract will state payment terms.  There are several options.

  • For a small project, you might agree to pay the contractor for materials, then pay the final amount on completion.
  • For larger projects, you could specify key payment milestones (such as “groundworks signed off”).
  • You could pay monthly based on percentage of work completed. “Percent complete” is a sensible measure of progress for a domestic project.  Your spreadsheet can help here too – add more columns to represent each month ready to add the percent complete for each activity. For example if the price to install the kitchen was £3000 and you estimate 40% of this was complete in June, it is reasonable to pay £1200 for this at the end of June. You then total all the June figures for all your cost lines to give the payment for June.

Do not agree to pay monthly at a set amount each month – you must pay for results, not time or effort. Otherwise, you could find that you’ve paid 80% of the money but the contractor has only completed 20% of the work.

Finally, the contract should state the retention and retention period for resolving snags after completion.  Reasonably, this might be a 5% retention paid 6 months from project end, provided there are no major snags outstanding.

 

here we revisit a glass conservatory installed 8 years ago

Other home renovation guides

We hope the notes above will help you to control the cost of house renovation.  Knowing the total cost, with a taut specification, a fixed price, and a sensible payment schedule, you shouldn’t go far wrong. You can read more about related topics elsewhere on our website by following the links below.

Property Renovation Guide.  This advice column describes what to expect from a property renovation. It leads you through the steps to a successful renovation and covers planning, specification, tendering, choosing a contractor, contracts and overseeing the work.

How to Renovate a Property.  An insight which includes a section on engaging professionals and the different skills they bring.

Cost of House Renovation.  This page and subsequent links show actual costs from our renovations since 2004.

Best wishes for a successful and affordable project.