LOFT CONVERSION

What basic checks should you make to see whether a loft is suitable for converting?

1. Check the current headheight in your loft space.

Rule of thumb: the higher the floor to ceiling height (to the underside of the ridge) the more the useful space you can add to your loft with an extension.

2. Check if your property has retained its Permitted Development rights.

Rule of thumb: Permitted Development Rights will allow you to fully extend to the sides and to the rear of your roof. However this is to a limit of a 40cubic metres for terraced properties and 50cubic metres for semi-detatched and detached properties. Likewise, Permitted Development Rights also apply for hip-to-gable loft conversions.

This will translate for a much more generous room sizes when compared to the typical allowances under the local authority planning rules. In general flats and properties in a conservation area have no Permitted Development Rights. This is to say that your local authority will approve a roof extension 2/3s of the roof height oand 2/3s of the pitched roof depth.

3. Is your roof a butterfly (V-shaped roof for a mansard loft conversion)?

Very different rules apply for butterfly roofs. As a matter of fact you might be able to add a full storey to your property by adding a mansard-type roof. Also, this applies to both houses and flats, whether you are in a conservation area or not.

Rule of thumb: Firstly, check the properties on eitherside of your property and on the same side of the street. Secondly, out of a row of 10no. properties, how many of them have had mansard roofs added to them? If the answer is more than 5no. then it is likely that your local authority will accept the addition of a mansard roof extension. If the answer is less than 5no. then obtaining an approval will be tricky.

4. Can your roof be extended?

Firstly, check with an architect or a building professional about the feasibility of converting your loft. Because not all lofts can be converted unless you lower the ceiling of the floor below. This will add complexity and costs and might make your project unfeasible or uneconomic.

On the whole, what you can achieve will vastly vary depending on your property and on your area. For this reason please speak to a professional architect and to your planners.

How much value does a loft conversion add?

What factors and type of rooms add the most value?

The value added will depend on the added floor area and where your property is the country.

In addition regional and local factors substantially affect how much value a roof extension adds to your property. For this reason, please have a chat with your local estate agents will be able to offer you expert advice on this.

Generally the added value is around 10-20% if you can create a new bedroom + en-suite area. For the most part this is something that is achievable at most times for typical 2-3bed properties. 

Generally speaking this can be achieved when properties have Permitted Development Rights and a 2.3m min loft headheight.

The loft conversion size

Firstly, always go for the largest roof extension and loft conversion you can get planning approval for. By and large this includes hip-to-gable loft conversions and rear roof extensions.

Secondly, a mansard loft conversion can add a whole floor to your property. However, the law of diminishing returns applies and for that reason once you have added a room or two the additional space will add less value / sqm added.

The relative £/sqm cost of adding this extra space is low. This means that if you commit to the project then it makes sense to maximise the area you can add to your property.

Indeed, once you know what is the maximum you can add then it becomes a question of how best to use this extra space. Also consider which type of rooms will give you the best value and best meet your requirements.

The type of room being added

1. Firstly, for houses with sufficient number and a good mix of bedroom sizes a loft conversion allows the opportunity to create a grand master-bedroom area with an en-suite and walk-in wardrobe areas. Also, if the space allows it even add a seating or kitchenette area. What’s more you can create a top floor “hotel suite” area as a special room for mum and dad.

2. Secondly, for a growing family a larger loft area offers the opportunity to create 2no. bedrooms areas and a separate bathroom.  For example, the separate bathroom that can be accessed either separately off the staircase landing or directly shared from the two bedrooms. Top tip: In this case, avoid arguments about who of the kids’ bedroom is larger: keep the size of the two bedrooms roughly the same.

3. Thirdly, another popular and valuable arrangement is the creation of a larger master-bedroom area while retaining enough space for a separate room in the loft. For example, this separate room can be used as a study or a gym space. Because this second space does not need to be large. Its value is in that it is a separate space that you can use flexibly when you need it.

Whether you lose any space for adding stairwells (ie lose a bedroom to gain a bedroom)

Nonetheless, sometimes you might need to sacrifice some space on the floor below to add the new staircase to the loft space. This is inevitable.

In fact, designing a new staircase is like a three-dimensional puzzle. The new staircase will need to comply with the current Building Regulations. And this means that the staircase should not be too steep or too narrow.

In fact, a good designer will minimise the impact of the new staircase on the floor below and locate the staircase where it allows you to maximise what you can achieve at the loft level.

All things considered, think of it as a Venn diagramme. And the new staircase will need to be exactly in the middle of the two floor plans and exactly at the right place for everything else to work well around it.

In conclusion, you rarely get to lose a bedroom to gain a bedroom. And when you do then the new bedroom tends to be much larger than the one you lost. In the vast majority of cases you will be able to gain a room or two by converting your loft space.

HOME DESIGN – Find a guide for ideas for your project.

• Side extensions London residential guide
• Rear extensions London residential guide
• Kitchen extensions London residential guide
• Roof extensions London residential guide
• Residential renovations London guide
• Mansard roof extensions London residential guide
• Contemporary extensions London residential guide
• Flat extensions London residential guide
• Garden flat extensions London residential guide
• House extensions London residential guide

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