Loft Coversions: Guidance for Professionals in Swansea and South Wales

Coverting a loft is not something that you can do anytime you want. There are rules and steps that you need to follow.

Your client will need to obtain planning permission if;

  • There is a change to the maximum roof height.
  • You use materials not in keeping with the property.
  • It exceeds 40m3 for a terrace or 50m3 for a semi or detached house.
  • The slope of the roof is altered.
  • You add a dormer window.
  • If the property is in certain conservation areas or national park.
  • If you add a veranda or balcony.


Before undertaking any loft conversions for either a terrace or semi- detached properties in Swansea, the home builder should check if they are obliged by the terms of The Party Wall Act 1996. This may mean a conversation with your clients’ neighbours. We urge all professional construction companies operating in Swansea to double check with their clients everything is legal before commencing work on a project.


It is more than likely that your client will wish to install windows on their loft conversion, so you need to ensure that they understand what this entails.

For a loft conversion to comply with Building Regs it needs to have an energy rating of C, as a bare minimum.

A lot of times both homeowners and building contractors in Swansea believe that the only windows that are available are UPVC. This is not the case. Timber windows are not only available, but they can be manufactured to the same standard as UPVC. Nowadays, wood windows may be double or even triple glazed and come with thermal insulation. Additionally, these can be found with a guarantee of 30 years plus. On top of the quality factor, is the simple aesthetics of a timber window, setting it head and shoulders above the run of the mill UPVC which has dominated in recent years.


  • DORMER WINDOWS At the top of the list are dormer windows. These are fit into the tilt of the roof. They are popular because they help bring light into a room. They can also be a decent size, for extra lighting and cosmetic appeal. However, these add onto your roof space, which might be pleasant aesthetically, but will cost rather more.
  • ROOF WINDOWS These are the more straightforward choice for homeowners who either don’t have a large budget or just want simplicity. They may also let in a decent amount of light. However, it is worth reminding your client of the need to shut them before going out – as they are literally cut into the slope of the roof and a freak cloudburst means a deluge when it rains!
  • BALCONY WINDOWS Although this is not for everyone, some clients might decide to go with a balcony, in which case French doors can be fitted to a loft conversion. However, as any construction company in Swansea will already be aware, these are not the cheap option!
  • ESCAPE WINDOWS An escape window should be able to let someone exit via it, should it be necessary. This means an opening of 0.33m2 and width of 450mm.

Don’t forget to make your loft conversion tally with all the building regs operating in Swansea council!

The Builders’ Basic of Building a Pitched Roof

Unfortunately in the course of their working life, our professionals have seen a lot of bodged jobs in South Wales!

It seems that some construction companies operating in the Swansea area do not even know the basics. To assist, we put together a glossary and guide to pitched roofs.


Did you know that almost a third of all heat created by central heating escapes through pitched roofs?

This is why it is vital for building contractors everywhere to understand the basics of thermal efficiency when planning or working on a pitched roof .

Insulation is key to the overall warmth retention in a home. Builders should be aware of the risks of condensation and poor ventilation within a pitched roof. This is because warm air can escape easily through the large beams which run along the structure of the roof.


BATTENS – these are the pieces of wood nailed to the rafters, which support the covering of the roof.

CEILING HANGERS – these support the ceiling joists.

COLLAR TIE – this is normally in the top third of the roof and situated in the middle of opposing rafters. It is meant to help stabilize a roof in heavy winds.

COMMON RAFTERS – these go from the eaves of the roof to the ridge and must be spaced 30-45 centimetres.

EAVES BOARD – this is the wooden board on which the lower roof materials lean on.

POST PLATES – these are there to support the rafters and are parallel to the wall face.

PURLINES – these are either steel or wood parts by the truss or wall. They help to support the rafters of the roof.

TRUSS – the truss is the frame which supports the top of the roof. It is made from triangular shapes. 

RAFTER TIE – not to be confused with a collar tie, a rafter tie is in the bottom third of the opposite gable rafters. It is there to help the rafters when there’s a heavy load.

RIDGE – this is the very top of the roof which is made by the inclined edges at the pinnacle of the slope.

VALLEY – this is where the two sloping edges converge and has an exterior angle of under 180 degrees.


VERGE – this is the edge of the roof, which is between the eaves and ridges.

FINALLY: whether you are a construction company or a sole trader builder in Swansea, it is important to know how to deal with a pitched roof.

Quite often existing roofs on clients’ houses will be in a poor condition and prone to leaks or worse.

It is vital to pay attention to the condition of the pitched roof, in all your undertakings.

How to Renovate Your First Building? Guidance for New Contractors

When working on home renovation in Swansea and the South Wales area we would urge all building contractors to pay attention to the following issues.

Planning Permission Home Renovation

Never assume your client has already obtained planning permission. Always double check before getting started!

Remember, planning permission is needed for renovation that are larger than 50m3 (or 40m3 for a terrace property).

It is also needed when the roof tilt is changed or the height of the roof is raised. Additionally, it is required for dormer windows and the installation of a balcony. This is not a comprehensive list. We would urge all home builders to check out the full list of regulations in Swansea here.  

Construction companies are advised to download the simple guidance issued by the council, which clearly sets out what is permitted and what is not. Different councils may vary, so take care to check correctly.

The Roof

There are normally two kinds of roof; trussed rafter roofs and traditional roofs.

Of the two, a traditional roof will be the simplestwhen in renovation. The trussed rafter roof will definitely require the input of a structural engineer, but we would advise all builders to get their recommendations regardless of what type of roof is currently in place.

Access All Areas

Unfortunately, some homeowners seem to think they will be just fine using the same retractable loft ladder they had before undertaking their loft conversion. It falls to the home building companies to set them right about this!

To comply with building regs, a loft conversion must have permanent access, but more than this, it also needs a minimum headroom of two meters for stairs.

Stair types which you may consider include alternating tread stairs, spiral staircases, and of course, conventional staircases.

Since space is so often an issue with resconstruction job, the first two options tend to work the best for most homeowners.

However if your client really doesn’t have the budget or the space for this then a ladder is permissible, just as long as it is a fixed one.

Safety Regulation for Contractor

Naturally, as a building contractor, you will be aware of the structural stability of both the roof and floor, as well as the rest of the property.

But additionally, certain task such as loft conversion will need to be fitted with a mains wired smoke alarm to comply with each state council regulations. And it also needs to have a window which is large enough to escape in a fire.


A lot of homeowners want to maximise the potential of their loft conversions by adding a bathroom, shower or WC.

As home builders, you probably know the best place for any loft bathroom is situated directly over the top of the main bathroom in the house. This is because drainage and piping already exists, as well as access to water.

Also remember that:

  • Baths can fit nicely under the eaves.
  • Toilets and basins need full headroom wherever possible.
  • The voids in a stud wall can be used for tap mixers and hidden showers.
  • Wet rooms can work in cramped spaces.
  • If there is no soil stack for a loo, you might consider a macerator. This can process the waste so it fits into the existing pipes – however, it can be noisy and needs to be used with caution.