Loft conversion has been proven to be not just the most cost effective way of increasing the space in your home, but also the easiest option to increase the value of the house.

Loft-3.jpgWhen running out of space in the house, the most common approach is finding a bigger house to move in. However, the loft conversion is proven to be the most cost effective alternative to house moving, while at the same time achieving the end goal: increase the space in the house to what you need.

When thinking of a loft conversion, there are many things to consider, so this guide intends to provide an easy reference for the most important aspects that need considering when making the step towards a loft conversion.


Question 1: Is my loft suitable for conversion?

There is more than one features that need considering in order to positively answer the question above.

The assessment for suitability of the loft conversion must include:

  • - Head height
  • - Pitch angle
  • - Type of structure
  • - Any obstacle, such as water tanks, chimney stacks, anything else that may impede the conversion.

All physical dimensions and structure can be assessed during a visual inspection of the loft.


Head height of the loft

The usable part of the loft needs to be of at least 2.2m high. This is measured from the bottom of the ridge timber up to the top of the ceiling joist.


Pitch angle of the roof: the higher, the better

Low pitch angle reduce significantly the usable area, due to the reduced height of the roof. Central height is higher when the pitch angle is higher, therefore giving more comfort.

Area of the loft can also be increased if the roof is redesigned to include dormers (if dormers are not used already).


Type of structure: traditional framed versus truss section

In a loft conversion it’s all about height and ensuring the structure is able to carry the load required.

The traditional framed structured, usually found for buildings build before 1960 is usually better suited for loft conversions because it has more structural input. Consequently, the space can usually be easily and relatively without much expenditure opened up to the requirements of a structural engineer.

The truss section type, which can be found in general in the buildings built after 1960, is a structure that made use of better technology and therefore allowed builders to build houses quicker. Because of that, there are no loadbearing structures underneath and in order to convert the loft into liveable space more work is required. Usually this would involve insertion of steel beams between loadbearing walls for the new floor joists to hang on and the rafter section to be supported on. A steel beam at the ridge is also required. Due to the additional works, expert advice is always required and consequently the cost of such a loft conversion is greater.


Low head height: what should I do?

The cost of a loft conversion is kept to the minimum if most of the requirements are met without additional work. However, not meeting those requirements does not mean loft conversion cannot be done.

If the height of the loft is under 2.2m, there are 2 options that can be used. Professional advice in both cases is mandatory.


New-Roof.jpgOption1: Raise the roof

Raising the roof is a feasible option however it comes with a high cost. It involves removing and rebuilding part or the whole of the roof to give it the right height. This option also requires obtaining planning approval, therefore proper consideration must be given.

In most cases scaffolding is also required, adding to the cost of the conversion.


Option2: Lower ceiling in the room below

Provided that the room below is left with at least 2.4m height, lowering the ceiling of the room below is a good option when considering a loft conversion into liveable space.

This is a messy solution as it involves removing the current ceiling and building a new ceiling, while ensuring the roof is not spreading.

This solution requires expert builders to ensure all jobs are done within Building Regulations parameters.


New joists for the conversion floor

It is highly probable that the current ceiling joists would be deemed inadequate for the new conversion, therefore new joists will be required.

The structural engineer will provide the exact specifications in order to comply with the Building Regulations.

The new joists run usually along the existing ones.



This is usually specified by the Building Control inspector.

Insulation can be done in one of the 2 ways: “cold roof” or “warm roof”. The “warm roof” insulation can be used with dormers, especially if there is also a flat roof involved.

Also continuity between roof and walls must be ensured, to avoid cold bridging.


Staircase: position and requirements

Ideally, the staircase needs to land in line with the roof ridge. In this case it benefits of the highest height and it makes best use of the available space.

The minimum height requirement above the pitch line is 2m. The height can be achieved by using a dormer or by adding a rooflight above the staircase.


Number of steps for the staircase

Current Building Regulations specify that the number of steps in a straight line cannot exceed 16.


Steps size and balustrading

The maximum step rise is 220mm however the rules are a bit more complex. In order to ensure Building Control accepts the staircase, care must be taken to ensure staircase and balustrading comply with all requirements.


Windows and dormers

Natural light and ventilation are a must for the new liveable space created.

The easiest and the most likely to be accepted without planning permission are the rooflights that follow the pitch line of the roof. The rooflights are fitted in the opening created in the roof by cutting the rafters, while reinforcing the other rafters.

Adding dormers can not only increase the amount of natural light but they also significantly increase the usable space of the converted loft.

Dormers and windows can also provide a secure fire exit, should a fire extend to the room below.


Fire safety: things to remember

When creating a liveable space through a loft conversion, suddenly the fire risk of the house is shared with the newly space created. It is important therefore that safeguards are introduced to limit the risk to the maximum possible.

For loft conversions, the fire risk regulations are very strict. For example, the loft conversions require a 30 minutes fire resistant floor to the loft and fire doors to all rooms. The fire doors do not need to be self-closing.

Fire alarms also need to be installed, with at least one to be mains operated, with a battery back-up. All alarms throughout the house have to be interconnected.


Room below: considerations

Depending on the room below the loft conversion, there may be a change of use of the room below.

The room below the loft conversion, where the staircase starts, need to be a communal transit area such as a hallway.

If the room below is a kitchen, a bedroom or a bathroom, consideration must be given to the layout of the floor below the loft.


How much my loft conversion will cost?

Due to the specific of each loft conversion, where houses and roofs differ so much between one another, it is very difficult to give a price without a prior inspection of the loft.

There are so many variables involved in a loft conversion, especially with regards to the raising roofs and lowering ceilings that a meeting with the builder to visualise the place and take measurements is an absolute necessity.


Force 10 Building Solutions: loft conversion in Doncaster, Rotherham, Sheffield and throughout South Yorkshire

Our experienced team has been successfully built loft conversion in South Yorkshire for a number of years.

When taking over a job such as a loft conversion we look at all factors impacting the work and we want to make sure we build a safe, cost effective liveable space.

Our team has significant experience in building liveable space through a loft conversion in Doncaster, Rotherham and throughout the whole of South Yorkshire.

Are you short of space in your home? Are you looking to increase the value of your home by adding more liveable space?

Give us a call on 01302 822 847 to arrange a meeting to see how we could help.

Alternatively contact us via our website and we will get back to you. 

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