An extension is the most popular trend for home improvements, especially when looking at making a substantial profit, a new survey commissioned by Direct Line Home Insurance has revealed.

Nearly half of builders agreed that extensions were the preferred choice, with a bedroom extension costing around £35,000.

However, 36 per cent of builders reported that loft conversions were one of the types of home improvement most likely to go wrong, with bathrooms and kitchens also cited as “likely to cause problems”.

The average asking price difference between a two and three bed house stands at £157,202 in London and £45,949 in Scotland, making extensions a hefty profit maker across the country.

“Extending homes or converting rooms to add light and space can add real value to a property, so can be worth the investment,” said Katie Lomas, Head of Direct Line Home Insurance.

“With the rising cost of house prices making it expensive to move, home improvements are a popular way to improve your living situation without breaking the bank.”

Just under 15 per cent of builders said access to light was the most common trend in home improvements, where large bi-folding doors, re-fixing exterior brickwork or fitting new skylights have been fitted to create more space.

Also, while 70 per cent of home improvements were completed on time and within budget, 26 per cent and 35 per cent of projects were found to have exceeded beyond the original budget and original timeframe respectively.

Other useful top tips from builders include:

•    Agree a quote beforehand - set aside a strict budget but allow a contingency in case of overspend to mitigate financial strain
•    Agree on a realistic timeframe upfront and remember to allow for contingencies
•    Make sure you understand what the project involves and be completely honest about previous work done to the house so builders can be prepared
•    Keep up regular communication with the builders
•    Have a contract in place to cover both parties and never hand over payment upfront
•    Use the same labourers from start to finish to ensure consistency
•    Make sure the builders are only working on your job and commit to working on it every day, rather than turning up as and when they decide to
•    Check your builder has the right insurance in place before any work begins

Katie concluded: “Homeowners should take note of the advice provided by builders, as spending a bit of extra time ensuring that they have an agreed plan and budget in place may significantly limit stress levels further down the line.”

100 UK builders took part in the survey in February this year.