A guide to loft conversions

26 August 2020

How to successfully repurpose unused loft space

Loft extensions are a great way to convert unused loft space into a liveable rooftop living room, guest bedroom, hang out space, home cinema or a study. A loft conversion can potentially add a significant amount of money to the value of a property (sometimes up to 20%). Homeowners tend to convert their loft spaces as it is a way to generate more living space without having to move home or build extensions that use up valuable outdoor space – which isn’t ideal for homes in cities as land is already precious. Construction work in a loft also tends to be less disruptive than a major extension, so it is usually less stressful.

industrial style loft conversion with large windows

Is the loft suitable for a conversion?

The first steps of a loft conversion project are to check whether the roof space is actually suitable for a conversion. The first things to check are the internal height, the roof pitch and the footprint. When measuring the height of the space, the measurements need to be taken from the top of the ceiling joist to underneath the ridge board in the apex – 2.5m or more is required to perform a loft conversion. As a general rule, loft spaces should measure a 5.5m x 7.5m footprint.

Once the loft space has been deemed suitable for a loft conversion the space needs to be given a purpose for the interior to be designed around. The interior will need to be carefully considered to determine what works will need to be carried out to transform the space. This space could be repurposed into a wide choice of uses such as an extra bedroom, a playroom or a multi-purpose space.

Storage needs to be considered early on in the project as there are many clever ways to create built-in storage, especially in the eaves. The interior design needs to be carefully planned as it may seem like the floor space is large but many loft conversions have angled ceilings (as they are in the pitch of the roof) which restricts movement in some areas. Most loft conversions make beautifully cosy spaces due to their angled ceilings, which are best suited for bedroom, offices and cosy spaces for children or adults to hang out in.

loft conversion with internal wooden beams

What are the design options for a loft conversion?

There are three types of loft conversions, these are internal loft conversions, dormer loft conversions and loft conversions that require a full removal and build. Internal loft conversions are the most popular choice for projects on a tight budget as they are typically the lowest cost and require the least amount of construction work. Dormer loft conversions are the most common conversion project because they provide additional, valuable head space without needed complex construction. Full loft removal and rebuild is the most expensive choice but the design possibilities are abundant and outstanding lofts can be created with this type of project.

Internal loft conversions usually include the installation of rooflights to allow more light into the loft. This is a cost effective method to convert the loft as minimal construction work needs to be carried out. Usually the construction work sees the addition of windows set into the slope of the roof, insulation added and strengthening works to the floor.

Dormer loft conversions sees the installation of dormer windows which increases the volume of roof space. Dormer windows typically extend out of the pitch of the roof at a 90 degree angle. These extensions are typically added to the rear of properties, but occasionally planning permission will allow them to be added to the side or front of the property. Single dormer loft conversions are usually permitted in conservations areas, occasionally two dormers are permitted which can be used to provide symmetry to the design while further increasing head space. A full-width dormer is an excellent option which really maximises space and creates a completely different feel to the other types of dormer extensions.

Roof removal and rebuild loft conversions require extension construction work as it usually involves the removal of one of both sides of a sloping roof being removed and replaced with a new structure that has steep sides and an almost flat roof. This kind of loft is known as a mansard conversion and requires planning permission. Another option is to install a pre-fabricated loft to replace the loft that was removed. This can be craned in place to form the shell of the new loft space and then the roof is constructed around it, but this requires extensive construction work.

loft conversion with a balcony and neutral interior

Where should I start with a loft conversion?

Once the purpose of the loft space has been determined, the homeowners should start by speaking to relevant companies to meet the interior design if the space. For example, if the space is going to be a bedroom with an en-suite bathroom then it’s best to discuss the project with a bathroom designer and an interior designer at the start of the project. This is also the case if the space is going to be a home cinema, smart home automation needs to be considered at the start of a project so speak to IndigoZest who will work closely with the appointed architect to prepare drawings and designs for the loft conversion proposal.

Drawings by architects are required to obtain the necessary approvals from local planning permissions boards if planning permission is required.

Invest in a quality builder or a specialist loft conversion company. Many builders and loft conversion companies are experienced in loft conversions, typically loft conversion companies provide a holistic service as they have departments for each stage of the construction. Many builders also have years of experience in loft conversions so they can sometimes offer a similar package to the larger loft conversion companies.

loft conversion with a wooden roof and window

Do I need planning permission, building regulations or a party wall agreement for a loft conversion?

Loft conversions do not often require planning permission, unless the extension works are going to extend the roof space or exceed limits (if a dormer is doing to be higher than the existing highest part of the roof or if the property is in a conservation area).

Building regulations are in place for loft conversions. Building regulations approval is required to convert a loft into a liveable space. They are in place to ensure; the structural strength of the new floor is suitable, there are stairs designed safety that lead to the new living space, the stability of the original property is jeopardised by the additional weight of the loft conversion, and that reasonable sound insulation in installed between the loft and the rooms below. There will also be fire regulations that will need to be adhered to.

Another consideration that needs to be made is whether the loft conversion is subject to The Party Wall Act 1996. This act comes into play when a wall that is shared by two neighbours is going to be affected somehow by the construction works.  The act requires notice to be given to the adjoining owners.

loft conversion with floor to ceiling glazing and gable end windows

Installing a staircase to a loft conversion

When converting a loft into a habitable space, a staircase will need to be installed. The design of the staircase is essential for the success of a loft conversion. It’s usually best to continue the stairs from the existing stairwell as it saves valuable space and creates a feeling on continuity through the home. Wherever the staircase is installed it will need to follow these guidelines:

  • Fire safetyfire precautions are one of the main concerns when it comes to Building Regulations as the highest number of fires tend to occur during the night. A part of the loft conversion will have to include mains powered smoke detectors in the hall / landing areas of each floor, as the exit from the highest floor level to the ground floor has be significantly increased.
  • Escape windows – Escape windows are large enough to allow people to climb through them and escape from a fire or to be rescued through them. They are required to have an opening (a clear opening) of 0.33m² minimum, and a width of at least 450mm. The bottom of the windows must be no more than 1100mm from the floor level to allow people to easily escape. Occasionally certain hinges are required, depending on the window system, which allows the window to open fully for escape routes.

loft conversion with armchairs by sloped windows

Glazing and ventilation for a loft conversion

Any new habitable room, whether it’s in a loft conversion or an extension, will need to provide ventilation. Typically, this requirement is achieved by installing double glazed opening windows or a rooflight that is the area equivalent to 1/20th of the floor footprint. These windows must also have trickle vents.

Structural alterations do not need to be made in order to installed rooflights or skylight windows. They are relatively easy to install into a pitched roof. Dormer windows are another option, and there are many design and configuration options for these. To see all the options for glazing in a loft conversion just speak to a specialist glazing company, like IQ Glass UK, who are able to offer advice on the best systems for the project.

As the loft is at the top of the property it is therefore usually exposed to the sun light for most of the day which can cause a lot of solar radiation and potential overheating within the loft space. Windows are excellent to allow fresh air inside to help cool down the space, however they also allow direct sunlight to penetrate directly into the loft. There are several ways to reduce solar gain, including a solar reduction coating to the glass or blinds. Grants Blinds offer bespoke blinds that can be installed within hidden fixtures, however this needs to be specified at an early stage of the project as the architect will need to include this within their drawings.

A successful loft conversion is an asset to properties as it can provide an excellent addition the home, with a huge range of uses.  To discuss your loft conversion project with any of our exhibitors contact us here.

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