QDo you offer a free, no obligation quotation?


Of course. We are more than happy to visit your property at a time convenient for yourself and quote for the required works.

QWhat is planning permission?


For domestic properties, planning consent relates to changes in the appearance or use of buildings such as an extension to a house, or a conversion of a house into flats. Planning should not be confused with the building regulations that are entirely separate. Planning can be one of the main hurdles to clear when thinking about making changes to your home and needs to be given consideration from the start. It may be possible that your project can be done within permitted development. Kompas London Ltd will be able to advise you of this during your initial visit.

QDo I Need Planning Permission?


As a general rule, if you wish to make additions or extensions that will affect the external appearance of your property you will need planning permission. More restrictions apply to flats and maisonettes than to a house. Internal alterations do not usually require permission, although you do need planning permission if you want to convert your property into separate dwellings i.e. flats or bed-sits. Not all loft conversions require planning permission.

If you live in a conservation area or your building is listed planning permission may be required for work which would normally not require it – always check with your local authority. If you have a situation which you think falls outside of these guidelines or are in any way unsure, it is best to contact your local authority who will give you the necessary guidance. Planning issues can be contentious and if you proceed without any required consents you may be required at your cost to demolish or significantly alter any development undertaken.

QWhat Is Permitted Development?


You may be able to make certain alterations on a house (as opposed to a flat or maisonette) without the need for planning permission. This is termed “permitted development” and it applies to an “original house” i.e. a house as it was first built, or as it stood on 1st July 1948 if it was built before that date. If an “original house” has not been extended (including loft conversions) you may be able to develop your property under these rights. As permitted development is subject to limits on height and volume, and has many permutations, we advise you consult your local authority and/ or an architect.

Your local authority may have withdrawn permitted development rights if you live in a conservation area.

QWhat Will I Be Allowed To Build?


Again, this is subject to many variables, and your initial enquiries should be directed to the local authority and an architect. You can gain a general indication of what is likely to be approved by looking at other approved development of properties around your local neighbourhood.

QWhat Is Building Control And Why/When Do I Need It?


Each local authority will have a building control office whose role it is to ensure that any building work conforms to building regulations, this includes the use of approved materials, design and construction methods. From a legislative perspective, building work is defined as:


  • The erection or extension of a building
  • An alteration to a building
  • A material change of use of a building
  • The provision, extension or alteration of a controlled service or fitting (drainage, boiler or other heated appliance, unvented hot water systems, mechanical ventilation systems) and replacement windows.

Internal alterations such as layout changes (even non-structural ones) may affect fire safety so it is worthwhile contacting the local authority building control office and discussing what you have in mind with them before you decide on the building work. Otherwise your new layout may require further work (for example, additional fire doors) that render your proposed changes unworkable or not financially viable.

General minor repair work involving replacing like for like does not normally require approval. If in doubt contact your local authority building control office.

This information is provided for your general interest only. Kompas London Ltd disclaims all responsibility and liability (including for negligence) in relation to use of the information on this site.

QWhat Is A Party-Wall Agreement and Will I Need One?


A party wall is an existing wall or structure shared with an adjoining property e.g. the common wall between two terrace houses. The term also includes the separating floor between flats (a “party structure”) or a garden wall (a “party fence wall” – does not include wooden fences).

As most loft conversions may affect the structure of a party wall you will need to notify all the adjoining owners of that party wall. Such work might typically include:

  • Cutting into a wall to insert a beam for a loft conversion.
  • Altering the height of a party wall
  • Demolishing and rebuilding a party wall (often to carry an extension)
  • Underpinning a party wall.

Minor works such as putting up shelves, or drilling and fixing plugs and screws do not require a party wall agreement.

Specific Questions About Loft Conversions

General Information

If you are preparing to carry out a loft conversion to your property, Kompas London Ltd is the right company for you. In this FAQ section, we will answer some of the most frequent questions relating to lofts, based on our previous clients’ experiences.
In case you cannot find your question below, please give us a call on 020 8590 0002 or send us an e-mail to [email protected], and our friendly team will happily assist you with any query you may have.

How much will my loft conversion cost?

Normally, a loft conversion will be priced between £30,000 and £50,000 depending on the type of the loft and its size. You can see here the different shapes and sizes of lofts that we build. Please do contact us and remember that we will help you come up with the most optimal design to fit your needs and budget.

How long will my loft conversion take?

The period of time necessary for a loft conversion to be completed is directly influenced by its size and complexity, but on average, based on our previous building experiences, it would take about 8-10 weeks to finalise the project.

How quickly will you start building my loft?

Kompas London Ltd can make the necessary arrangements in as little as 2 weeks before starting the construction project. This timescale takes into account that you have already obtained all the required documents: drawings, structural calculations and party wall notices. In case you don’t have the plans, they will take around 2 months to be drawn up. The same is true for the building regulations drawings, structural calculations and party wall notices, although the time to make these is variable. In summary, the construction phase will begin after these intermediary steps are completed.

How long will it take to get plans drawn up?

We can make the drawings for you within 2 months or less, depending on the complexity of the project.

How long will it take for my plans to be approved?

Although the time of approval may vary from Council to Council, generally it takes about 8 weeks for a decision to be issued. In case a revision is required by the Planning Officer, the process may take a little longer.

What is a party wall agreement and will I need one?

In the case your property is connected to another one, so that they have a common wall, a party wall agreement will be required. The interested neighbour will have to be informed about the building works by way of a party wall notice, at least two months before the construction begins. The party wall agreement can be defined as an agreement between the two neighbours regulating their relationship in case of a potential conflict. At Kompas London Ltd, we can advise you on this matter and put you in touch with one of our certified party wall surveyors.

What is permitted development?

If your property is not in a conservation area or is a flat, you have permitted development rights, under which you can develop your loft without having planning permission. This should however be within certain constraints. Semi-detached properties and the detached ones are allowed to be increased by 40 cubic metres, whereas terraced properties can only have 40 cubic metres of space added to them.

What is the difference between permitted development and planning permission?

When you are submitting your proposal for planning permission, the Council is free to approve or reject it, following the requirements of the local development plan. The permitted development is not subject to this kind of decision, as you are only asking the Council to confirm that your proposal corresponds to the criteria of permitted development. If this is the case, you will be given a Lawful Development Certificate before the commencement of building works. This certificate is not mandatory, so you can start the works without having obtained a Lawful Development Certificate.

How much head height do I need in my loft to be able to convert it?

There are certain head height requirements you must adhere to in order for your loft conversion to be compliant. As a rule of thumb, you need 2.2m between the top of the floor joist of the loft to the bottom of the ridge beam.

Can I convert my loft?

You can check your ridge height with a standard tape measure, which will give you an indication if the space is convertible. But the only real way to know for sure is to invite one of our specialist surveyors to fully assess your property. Our specialist surveyors can provide a  loft conversion site visit, no matter what area of London you live in.

What other services do you provide beside loft conversions?

We carry out all types of construction works, including house extensions, full house refurbishment, basements and new build projects. It is common that we do the loft conversion while extending the house, or fully renovating it. All options are available to our clients.

Can I visit some of your old projects you have completed in my area?

Because we cover all London Boroughs, it is highly probable we have already completed several projects in or around your area. Thus we are happy to share any references we may have, so that you may contact them or visit their properties.

How long will my quotation be valid for?

3 months.

Complaints Procedure

If you are not happy with Kompas London or any of its operatives, you must make a written complaint and email it to [email protected] or post it to:

Complaints (Osman)
Kompas London Limited
16 Electric Parade Seven Kings Road

Otherwise, your complaint will not be considered. All written complaints will be logged. You will receive a written acknowledgement within three working days. The aim is to investigate your complaint properly and give you a reply within ten working days, setting out how the problem will be dealt with. If this is not possible, an interim response will be made informing you of the action taken to date or being considered.

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