You’ve weighed up all the options and your heart is set on a loft conversion, adding value to your property by transforming a fantastic space generally utilised for storing junk and the Christmas decs. But, before you can get that dream bedroom with ensuite, playroom, workspace or gym underway, here are five key things to consider.

1. Is my loft suitable for conversion?

There are three things you need to check here, as recommended by the Master Federation of Master Builders. 

Internal height of the existing loft – Measure from the bottom of the ridge timber to the top of the ceiling joist. This should be 2.5m to suitably convert. However, we have converted lofts around 2.25m, which is something we can discuss.

Pitch of the roof – this should be 30 degrees plus.

Footprint of existing loft space – We have worked on narrower lofts, but the general rule of thumb is that internal walls should measure 5.5m side to side inclusive of chimney and 7.5m front to back. 

2. What are the main types of loft conversion?

Factors including the type and age of your home, as well as your budget, will have a major influence on which type of loft conversion you go for. There are four main types and, if you choose and a survey gives the thumbs up, some of these types can be combined.

Four main types:

Roof light – cheapest and least disruptive with no changes to shape of roof

Dormer – extension that protrudes from slope of roof, flat-roof dormers being the most popular for adding extra headroom and floor space (typically, most dormers can be built across the full width of the rear of a house under Permitted Development where, subject to criteria, planning isn’t required). A flat-roof dormer can be:

  • Rear

  • Side (if your house has the highest point of the roof slope running along the middle from front to back)

  • L-shaped (if your house also has a rear addition)

Hip-to-gable – extends sloping ‘hip’ roof at side of property to create a vertical ‘gable’ wall for more loft space. For detached and semi-detached houses only. These can be combined with a dormer or a mansard.

Mansard – runs along length of house roof and alters angle, making it almost vertical. Most expensive, but will give you masses of extra space. You can choose from:

  • Rear
  • L-shaped (if your house also has a rear addition)

What gives the mansard its character is that the fascia is at a 70 degree slope and the cheeks are, typically, built up in brickwork. Full width or L-shape mansards are, typically, granted planning permission in some areas where full width dormers aren’t permissible.

3. Do I need planning permission, building regulations or party wall agreement?

We’ve all heard the stories of homeowners who start extending away with planning permission, only to have the courts rule that it needs to taken down or the homeowner should be fined to the hilt for flouting the rules.

The good news with loft conversions is that planning permission is not normally required, unless you are extending the roof space or exceeding specified limits. For example, if a dormer is higher than the current highest part of the roof or you live within a conservation area. Just in case, it’s always best to check with your local planning department before you start.

Either way, you will have to adhere to building regulations with your loft conversion. This is to ensure things such as structural integrity, from the new floor to the stairs to the new room(s) to reasonable sound insulation. 

You will also need to comply to fire safety regulations and whether your project is subject to The Party Wall Act 1996. If so, you must give adjoining owners notice.   

4. Will my building quote include additional extras?

It’s absolutely crucial to check whether additional extras such as lighting and fixtures and fittings are included in the quotes you receive. Often, homeowners receive quotes from companies which appear cheaper at first glance, but do not include all the additional extras you desire e.g. dimmer switches, LED lights, USB points, shaver sockets, aerial points etc.

As well as a realistic quote for the building work, you should also get one that covers off all the details to provide a much more accurate idea of what your loft conversion will cost you from the word go, representing your budget and aspirations as closely as possible when you are making your initial decision. 

Make sure you have factored into your budget additional and potential upfront costs such as a central heating and water mains upgrade (if required), a new fuseboard (if required), Party Wall surveyors’ fees (if required), and Building Control and relevant planning application fees.

Other important costs to factor in are sanitary ware for the bathroom, carpets and flooring, joinery and wardrobes, bathroom tiling, decoration, curtains or blinds. Satellite or aerial realignment might be needed at the start and finish of the job, depending on scaffolding.

One of the first things you need to do is discuss the building work with your neighbours and ask them to sign party wall notice forms. It’s always good to advise your neighbours you are having building work out of courtesy.

Think about what you’d like in your new loft space BEFORE you meet your build team. This will help ensure there are no delays with any red tape.

Once you’ve confirmed your loft conversion, choose your bathroom and sanitary ware and ensure it is delivered in time. 

When your loft conversion is imminent, clear everything out of your loft, as well as any pictures, mirrors and other loose objects from your hallway, landing and stairs, and move existing furniture. In addition, don’t forget to ensure there is enough parking for builders and fitters, and that you have any necessary parking permits.

With decades’ experience in the property development sector, James Lebens is managing director of Make Room Lofts, which caters for clients with all types of aspirations and budgets in North London and the surrounding areas.