Getting a quote as accurate as possible for your building project and being aware of other costs is really important for budgeting purposes. In some cases, things are uncovered as the build progresses which can potentially add extra costs. Make sure you communicate clearly with your building contractor so that all parties know what to expect from the outset. We have looked at 5 expenses that are commonly overlooked by home owners when budgeting for their project. If you are considering an extension, new build or a renovation project, have a look at the top 5 on our list.

1 – Assuming your current heating system can cope with the extra load of your new home extension or building project: a dangerous game.

It stands to reason that your current hot water arrangements will have been designed and specified for your existing space, but it may not be sufficient once your footprint has expanded.

Equipment that has been happily chugging along serving 8 radiators, 2 bathrooms and a kitchen may well protest at the thought of your impending building project. Expecting that you can add radiators, wet underfloor heating and extra bathrooms to the current system may be optimistic.

Communicate early on with you chosen building contractor and request that their specialist appraises your current setup. It may well be that they feel that you will need an upgrade or replacement system.

This is an expense that is often overlooked when budgeting for renovation and home extension work. Speak up early and discuss this with your builder.

2 – Under-estimating the impact your extension and renovation work will have on your exterior space.

It starts with the rumble of diggers and dumpers and within a week your garden resembles something a hippo would be proud to call home. Then come the network of drainage trenches and before you know it, there is a gaping oozing wound through your drive.

Your extension may be finished internally but believe me your garden will suffer from your home improvements. It is impossible to build an extension and not impact the exterior space. If you don’t plan properly for the exterior building work and consider it as an essential part of your project you may well be frightened to look out of your beautiful new windows from your shiny state of the art kitchen. Overlook this significant expense at your peril, or yours will be a life of tiptoeing through mud to your car and sunbathing in a swamp!

Communicate with your building contractor at the planning stage and get a realistic idea of the collateral damage your renovation will make to your outside space and then build in a realistic budget for the exterior building and landscaping works. Getting a concise plan and scope of works for your exterior work is the way forward.

3 – Whoops…we forgot about professional fees associated with our extension building project

Given the significant cost of building an extension, surely in the grand scheme of things a few engineer’s bills won’t make much difference to my building budget, will they?

Professional fees can really add up and factoring these into your build budget is paramount. Planning approval is not the end of your fees. Typically, when you are extending your home your architect or designer will work with a structural engineer to produce the building regulations.

By the time you are ready to start your building project, typically you will have paid for planning drawings, planning submission, building control issue drawings, building regulation submission and the building inspector’s fee (private of local authority). Depending on your particular project, you may also have to have a drains test, soil test, party wall survey, environmental survey: these are all costs that you should consider before embarking on your building project.

In addition to the essential and basic fees, you may want to engage the services of other professionals perhaps an interior designer or a garden designer would take your renovation or extension from good to great.

4 –  Remember storage and removal costs are a part of your building budget

Regardless of whether you remain on site or have to move out, there will probably be stuff to get out of the way. Stuff, stuff, stuff. We all have lots of stuff and whether it’s precious or simply in the way, it needs to be moved out, stored and moved back. This is so often overlooked and depending on the extent of your building work you may have to consider hiring a van and taking on storage space. If you are undertaking a comprehensive renovation and extension project you may have to leave your home completely clear. Don’t overlook the stuff!

5 – Internal collateral damage caused by your new extension

Assuming that adding an extension to your home is not going to impact neighbouring rooms/areas is optimistic. More often than not an extension knocks onto the rooms adjoining. It can be like an expensive game of dominos.

Have a frank conversation with your building contractor and be realistic about the collateral damage. Walls and floors are the most common victims of house surgery.

As with all building projects, yours will be as successful as the planning and your team. Do the leg work, communicate and be realistic. The odd spreadsheet won’t hurt either.


Get in touch to discuss how we can help you turn your dreams into a reality, we would love to help you.

Our expert builders at A. Mann Building Contractors are here to discuss your building project in Kent and Sussex. Please call us on T: 0330 128 1021 or email us E: ambuilding@hotmail.co.uk