Maintaining Your Property
A house extension or a loft or garage conversion can give you more space, and often more value, for less than the cost of moving. It is also expensive, disruptive and slow to deliver, so it pays to test the idea first: will it add value, which option fits, and what could go wrong once building starts?
Why it matters
Extra space
Building out or converting unused space usually costs less than moving to get the room you need, and done well it can raise what the property is worth.
Three costs
Disruption, time and money. An extension is rarely just the build: materials, windows, doors and furnishings all add up, and the work has to be lived around.
Ceiling price
The most important number nobody checks. If your area has a ceiling price, spending beyond it may never come back to you when you sell.
Before you commit
The extra room may be exactly what you need now, but plans change and you may want to move within a few years. If the work has not lifted the property's value, judged against the ceiling price for similar homes nearby, an expensive and disruptive build can turn out to be poor value when you sell.
Compare a single-storey and a two-storey option before you commit. A second storey adds cost and disruption but often more usable space per pound, and the money and the practicalities rarely point the same way.
Some problems only show up once work is under way. Check parking (how many cars the drive still holds), how you will get in and out and live in the house during the build, and what happens to your plans if planning permission is refused.
Budget for everything beyond the shell: windows, doors, flooring and furnishings. Many owners fund an extension with a loan or by remortgaging, so check that the work will add value before taking on that debt.
Before plans are drawn, work out how builders, deliveries and machinery will reach the site. A design that cannot be built without dismantling a boundary wall is a design that costs more than the drawing suggests.
Site factors
Converting a room
A conversion reuses space the house already has, most often a garage or a loft. As long as you are not also enlarging it, there is usually no demolition or heavy structural work.
Because the space is already part of the house or its driveway, refusal is uncommon, unless the deeds or an earlier planning condition say otherwise. Check those documents before anything else.
Of the ways to gain space, a conversion is usually the cheapest: less than moving, less than building an extension, and it can still add value to the home.
The catches
The headline cost is rarely the final cost. Fees, professional advice and unforeseen work all sit on top of the build quote.
Less likely is not the same as impossible. Each property has its own planning permissions and circumstances, and those govern what you are allowed to do.
Access to other rooms, or to garden areas connected to the room being converted, can be restricted for the duration of the work — which causes real disruption to a household.
Depending on how complex the job is and what state the building is in, you may need surveys, upgrades or repairs before work can start.
What we look at
A survey tells you what condition the property is genuinely in before you spend on plans and materials. Defects that surface mid-build are far more expensive than defects found beforehand.
We assess the factors around the building that affect what you can safely build — soil conditions, the state of the drains, and the trees and vegetation near the proposed foundations.
Where a property has already been extended or converted, we look at how well the work was carried out and whether the new structure was properly tied into the original building.
Common questions
Only if it adds value relative to the ceiling price for similar homes nearby. The space may suit you now, but if you sell later and the work has not lifted the value, you may not get back what it cost.
Price up both. They differ in cost, disruption and usable space, so choose the one that makes sense financially and practically for your property.
Parking and access are the usual ones: how many cars the drive will hold and how you will live in the house during the work. Also plan for a possible planning refusal and for how builders and deliveries will reach the site.
Everything beyond the shell, especially windows, doors and furnishings. Many owners end up taking a loan or remortgaging to fund the work, so the full figure matters more than the builder's quote alone.
Soil type, services, surrounding trees and vegetation, any past flooding, and rights of way can all affect what you can build and what it costs.
Usually, yes. A garage or loft conversion reuses space the house already has, so as long as you are not enlarging it there is little demolition or heavy structural work.
Often not, and refusal is uncommon because the space is already part of the house or driveway. Check the deeds and any earlier planning conditions first, since some properties have restrictions.
Yes. A second opinion from a surveyor or other professional before plans are drawn is far cheaper than redesigning, or rebuilding, once work has started.
Any questions?
Our surveys are carried out by Professionally qualified surveyors and give owners a clear picture of a property's condition before they commit to building work. Findings help you budget realistically, plan around what the site allows, and avoid the costs that only surface once the work has started. We can also prepare the plans and drawings and building regulation drawings for the project.
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