Andrew Milne: Beware of a flawed plan when adding to floorplan

Andrew Milne of DM Hall Chartered Surveyors advises a reader on whether or not to make an ambitious extension to their family home

Andrew Milne

Question: Our daughter, who graduated a year ago, is now living with us in our house in Edinburgh because she can’t afford to move out. With this in mind, we are thinking of making some changes to our house to give everyone their own space.

It is big enough. We have four bedrooms, two bathrooms, a sitting room, a study and a large dining-kitchen area which would be untouched. But we also have a first-floor room used for storage, which is above our integral garage and utility room.

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These three rooms could be used to create a one-bedroomed flat with its own entrance. We would need to line the garage, which would become a sitting room, replacing the up-and-over door with patio doors.

The adjacent utility would be refitted as a kitchen. A spiral stair could be installed to go up to the new bedroom without adjusting walls, and we’d create an ensuite shower. Two doors to the main house would be locked but not blocked.

We have a budget of £20,000, which we think would be just enough, and affordable if we charge our daughter a nominal rent. However, would it add to or detract from the value of the house?

Losing the garage and utility room would necessitate some major reorganisation, but if we felt it was a good investment we would go ahead. We plan to stay for at least another five years, which will hopefully see all of our kids successfully turfed out of the nest for good.

We don’t live in a very high value area. The house, which has a big garden, is currently worth about £350,000.

Answer: The first thing you must ask yourself is: “Why am I doing this?” It is of primary importance that you are clear and focused, and you understand the imperative in any conversion or extension is to add value to the property.

Will you achieve that aim? Without seeing the detailed plans, it is difficult to say, but it is worth initially looking at the factors that currently weigh for you and against you as you embark on this ambitious project.

On the plus side, the Edinburgh property market is on the boil at the moment. Seasoned professionals, normally restrained and cautious in their assessment of market conditions, simply say that it has “gone nuts”.

There has been huge demand and a continuing scarcity of supply, which is intensifying competition among buyers to an almost unprecedented degree. I know of a £1 million house in the city which sold to an out-of-town buyer on the strength of a video tour. The buyers didn’t even see the property.

So many viewers are pushing to inspect homes in the current climate that estate agents are having to screen them to weed out people who do not have adequate mortgage funding in place, or who are restricted by their place in a chain.

The downside is that, even if you do decide to start work on the project, you may well struggle to find a builder. Competent trades people are booked up for the rest of the year. On top of that, builders themselves are being delayed by a continuing shortage of materials, the costs of which are also soaring.

I am not sure, on the budget that you are talking about, that you have fully factored how much it costs to re-fit kitchens and bathrooms these days, and refits need to be compliant with building and fire regulations. Heating systems, too, would have to be split or separated and you may need to upgrade your boiler system.

While I understand your wish to create a personal space for your daughter, you need to consider keeping the work general enough that it can be adapted in the future to another, different set of needs.

For instance, a granny flat can be attractive to buyers, but the access is important for a senior citizen so, looking ahead, a spiral staircase is not a serious proposition.

Generally speaking, a spiral staircase may be aesthetically-pleasing, but it is rarely a good practical option.

Could the redeveloped space be used in future as a standalone office? Home offices – for the obvious reasons of the past year – are very much in demand and can add significant value, especially to an already quite roomy property.

Seeking good advice at the start is vital and will save you a fortune in the end. An architect will be able to guide you on how to drive the project towards the maximum net increase in value. And they will also show you how to merge the works into the general flow of the house, which will be particularly important when selling on.

It is at this stage that you will have to check and investigate the planning permissions required – and the cost of these permissions, which can be hefty.

You should also be looking dispassionately at the technical hurdles you will have to overcome, and whether or not they might derail the project.

Do not close your mind, either, to the viability of alternative solutions to the space problem. For instance, could you simply convert the garage? You say you have a big garden. Is there potential for a small living unit there?

You are thinking of spending quite a lot of money. From a purely economic standpoint, there is no justification for doing this if you are not going to recoup your costs. Remember that the market is fickle, and that it can cool down just as quickly as it has heated up.

In conclusion, I would argue that the considerations above may well prove to be academic since I don’t think the £20,000 budget which you have allocated – notwithstanding the possibility of some small rent contribution from your daughter – would be anything like enough for what you have in mind.

Almost all projects of this nature go over budget – just think of the Grand Designs programme on television – so if this is likely to cause you financial embarrassment, you might be well advised to cut your coat to suit your cloth.

Fact file

Consent You need planning permission for any new development. The law says that the definition of “development” includes any building, engineering, mining or other operations in, on, over or under land. It also includes changes in the use of buildings and land. Your council will be able to tell you more.

Inside job However, planning permission is not needed for work which only affects the inside of a building – but, if it is a listed building, you may need listed building consent to make any alterations to the property’s interior.

Green light Some changes to existing developments, such as certain house extensions, are classed as permitted development and don’t need permission from the council.

Double check You should always check with your council’s planning department about whether you need to apply for planning permission for building work. Discussing your plans with them before you make an application is recommended.

Andrew Milne is a partner in the Edinburgh residential office of DM Hall Chartered Surveyors

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