Loft conversions

KPD Construction is a specialist for new builds, extension works and loft conversions and all associated works like carpentry, tiling, electrical works, plumbing & heating, roofing etc.

We pride ourselves on the straightforward, efficient and professional way in which we deliver our projects on time and to budget.

We will gladly offer a free service in terms of pre-construction advice and revisit your design if you feel it is needed before construction. Please feel free to contact us.


A loft conversion allows to turn the roof space into usable and habitable space which else is underutilised. This is a popular project to get added space and adds value to any property.

Benefit: Converting an existing loft space can be an easy and cost effective way of increasing living accommodation in most houses.



Dormer Loft conversion

A dormer construction in loft conversion project allows creation of space and headroom. A dormer construction is usually a structure built from a sloping roof to form a vertical window. Dormer construction vary in sizes and roof design. A simple illustration of the types of dormer is displayed below.

Roof Types

Dormer Conversion

Dormer Conversion

The most common dormer construction are Gable fronted and flat roof. The former look much more attractive but they often do not give as much internal space and will cost more to build due the extra complexity


Mansard Loft Conversion

A Mansard construction can be described a big flat roof dormer construction except that the vertical wall of the construction is designed to be slopped inwards, giving an appealing look. Mansard construction in a loft conversion is common in inner London areas, where generally the trend is to follow existing Mansard conversions within the locality.


Roof Light Construction in a Loft Conversion

Roof lights can then be installed easily with minimal disruption. They are particularly useful in building within conservation areas or listed building. It also suits smaller loft conversion which can be used for a single bedroom, children playroom or study etc. This is ideal where there is sufficient height within the existing loft space.


hip-to-gable conversion

A hip-to-gable loft conversion is about demolishing the hip end (the sloping side) of a roof and reconstructing it with a gable end wall. Hip-to-gable end conversion is mostly found in semi-detached properties and lots of end of terrace properties.

The conversion requires adds a significant part to the roof and provided that the additional volume added is less than 50m3, planning permission is not needed.


Planning permission for loft conversion is not needed if

  • The roof space created will not exceed 40 cubic metres for terraced houses and 50 cubic metres for detached and semi-detached houses.

  • No extension beyond the plane of the existing roof slope of the principal elevation that fronts a highway is proposed.

  • Materials to be similar in appearance to the existing house.

  • No part of the extension to be higher than the highest part of the existing roof.

  • No Verandas, balconies or raised platforms are proposed

  • Any proposed side-facing windows must be obscure glazed and non-opening unless the parts which can be opened are more than 1.7

  • metres above the floor of the room in which it is installed.

  • The roof extensions (apart from hip to gable) is to be set back by minimum 20cms from the eaves.

We recommend that you check with the Local Council before you undertake any construction, or call us for free advice.

In listed building/conservation area circumstances, consents may be required for your loft conversion and no works should be commenced until approval has been given by the planning department.


The building owner must make a building regulations application & pay a fee for the proposed works. KPD Construction will deal with this on the owner's behalf. All work must comply with the Building Regulations and the technical design and constructional requirements of the current Approved Documents A to P and Regulation - 7 Materials and Workmanship.

KPD Construction will liaise with your local Authority and meet the requirements of the LA Building Control/Certifying Body, giving required notices of stages of works as required by the Building Regulations so that the Local Authority can inspect the work as it progresses on site. When the project is satisfactorily completed a Building Regulations Completion Certificate will be issued showing that the project has been independently inspected and that it complied with the Building Regulations.




Typical plan layout of a loft conversion with dormer pitched roof



Typical section through a loft conversion with dormer pitched roof


Typical section through a loft conversion with dormer flat roof

Typical section through a loft conversion with dormer flat roof


In terraced or semi detached houses, the conversion is usually affected by the Party Wall Act. In such a case, you may be required to give your neighbour the required notice under the Party Wall Act. KPD Construction will deal with this on the owner's behalf

Two months notice in writing is to be given to adjoining owner(s) for the following works to an existing Party Wall:

  • Support of beam
  • Insert DPC through wall
  • Raise wall or cut off projections
  • Demolition and rebuilding
  • Underpinning
  • Insert lead flashings

Excavations within 3 meters of an existing structure where the new foundations will go deeper than adjoining foundations, or within 6 meters of an existing structure where the new foundations are within a 45 degree line of the adjoining foundations.


It is of critical importance to make an assessment of how feasible would converting a loft be. The procedure would be quite simple and would require inspection of the existing roof space and the dwelling as a whole by an experience trader.

In general the following would be considered:
The existing roof structure. Its size and form- The existing roof structure, its size and design and construction features is a major item to be considered for suitability. Timber pitched roofs construction with gable ends walls are in general more easy for conversion. Th econversion will require a new structural beam being introduced at ridge level.

In hipped roofs scenarios, the structural designs may be more demanding and structural calculations will be needed by a qualified structural Engineer.

Existing timber structure: Existing timber work should be in a good condition and should not show any sign of deterioration or biological attach such as insect or fungal attack. Careful inspection would be needed and in case of any defects found, consideration will need to be given in the design for the conversion. Again, you will need to ensure that a suitable qualified and experience specialist.

Head room availability- This is critical to any conversion and is measured vertically from the finish level to the underside of the proposed horizontal or sloping roof. A clear headroom of 2.0m minimum would be required in order for the conversion to be compliant with building regulations. The same requirement applies for the stairs. Hence, in cases where there is not enough headroom, lowering the existing floor level can be considered for feasibility. Greater ceiling heights are better and would make the conversion feel more spacious.

Ceilings- To the underside of the new storey floor should achieve 30 minutes fire resistance. Normally 13mm plaster board & skim or sound lath and plaster in older houses will achieve this, otherwise additional upgrading will be required.

Existing Roof Coverings - As for the timber, any covering should be in good condition and weather tight. In not the case, consideration is to be given for reconstruction which need to ensure that new detailing are compliant with building regulations and any replacement are to match existing as required by planning. There is a variety of products which can be used and it is to be ensured that in all cases, manufacturer's instructions are followed.

Means of escape- Any two storey conversion will be deemed as a three storey house and this will imply additional protection for fire safety. Hence the stairs from the new loft to the final exit at ground floor level will require fire resistant construction with all doors to habitable rooms changed to fire doors such as to form a fire proof corridor system. Usually, this should achieve 30 minutes fire resistance. In actual construction, use of 13mm plaster board and skimming or the use of sound lath and plaster will enable compliance with the 30 minutes fire resistance requirement.


Converting an existing loft space can be an easy and cost effective way of increasing living accommodation in most houses. This guide provides useful guidance on how some of the technical design and construction requirements of the Building Regulations can be achieved where the loft space of an existing one or two storey dwelling is being converted into habitable accommodation to form an additional storey to the dwelling.


This type of work can be complex and unless you are experienced in construction you will need to get some professional advice from the following:

  • Appointing a suitably qualified and experienced property professional who will prepare drawings and designs for your proposal, obtain the necessary approvals and if required they will also help you to find a suitable builder and manage the project for you. KPD Construction has the necessary knowledge, expertise and skills to undertake that for you.
  • Appointing a specialist company such as KPD Construction will offer a one stop shop for this type of work, and will prepare drawings and designs for your proposal, obtain the necessary approvals and carry out all the necessary construction works to complete the project.
  • Using an experienced builder such as KPD Construction


How do we know if we our loft conversion is feasible?
The key here is about the headroom. A height of about 2.5m at the ridge would usually be satisfactory. Else we will need to consider lowering the existing floor.

Do I need Planning Permission for a loft conversion?
Most of loft conversions do not need Planning Permission (please refer to section ***above for permitted development rights).

How long does a conversion take?
This will depend on the size, structural implications and design, but generally in most cases, we take approximately 3 weeks to build the structure watertight and another 2 to 3 weeks to complete internal works and second fix etc.

There does not appear to be anywhere for the stairs to go.
Placing of stairs is a key aspect in the design of the loft conversion. With our expertise and skills, we don't anticipate this to be a show stopper..

Will a loft conversion really add value to our property?
Any compliant loft conversion will certainly be a value added. In accordance with Building Society literature, loft conversions is regarded as one of the best ways to add value to a property or to your sweet home.

How do I know that the work that you do is structurally sound?
As a professional construction company specialising in loft conversion, we will send out our qualified Engineer to do a structural appraisal and hence prepare structural calculations, drawings and reports as necessary for construction. This will be submitted to the Local Council for approval and we will only start construction after all the necessary approval has been given by the Authority In addition, all of the work that we do is checked and approved by your local building inspector to conform to building regulations.

What if there are tanks in my roof?
Most of these are out of use and will be removed safely. However, if they are live, we will get them decommissioned by gas-safe registered professional and if needed a new pressurized system can be installed. This should not in any case hamper a loft conversion or take loft space.