House & Home Extension Builders North London

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Home Extensions North London

Home Extensions North London

Ever wanted to know how a home extension is built? Below you'll find details of the process.


If you haven't already got plans, working closely with you, we will help you to plan your extension, taking into account any budget you've allocated and the existing structure, style and size of windows and doors, style of roof, what use you wish to put the new extension to, as well as any other factors that are relevant. If your new home extension will require planning permission (which we can advise you on), then it may help your case if plans are drawn up by a qualified architect.
We have devoted a whole section to obtaining planning permission, to find out more, click HERE.
To find out more about building regulations click HERE.



Once you have all the permissions and plans, we will quote you for the work on your new home extension.

Once the costs, work schedule, and staged payments are agreed between us we commence the building works.

Working to the plans that have received building regulation approval, we first mark out where we need to dig down to create a channel into which concrete will be poured to form the solid foundation base for your new home extension.


The soil we dig out is put onto a skip and taken away for land-fill puposes.




Any new drainage or waste pipes required are installed in their own dedicated dug-out channels and then the channels are refilled with soil or concrete depending on the specified requirements.



The "QuickMix" liquid concrete for the foundations arrives.


The foundation channels are filled with concrete which is then left to 'cure' naturally.


This 'curing' process doesn't take long with modern materials and there is much other work that needs to be done in the meantime while the foundation cures.


If a through extension is required, supports ('acros') are put in place to bear the additional weight before an aperture is knocked through the existing walls.


Steel beams and steel supports with the load bearing characteristics specified in the building regulations are then put in place so that the acros can be taken away.



Once the concrete foundations have hardened to a prescribed level, the construction of the new walls of your home extension can begin.


We only employ the best, time-served bricklayers, most of whom have been with us for many years.




Once all the walls have been built to the required height, the roof is constructed on top of the new extension walls in accordance with the load bearing requirements specified in the plans and building regulations.




Window and door openings are prepared in readiness to accept the new window frames and door(s) which then arrive and are installed.




Any existing drainage is boxed so that it will be hidden and not appear unsightly when the extension is finished.

The windows and doors are installed.

Electrical cables are run to provide power to any lights and sockets specified.

Plumbing is installed for any radiators required.


The floor is then layed, concealing any underfloor plumbing and wiring and the walls and ceiling are faced with plasterboard and then skimmed to provide a smooth finish for any further decoration that may be required.




The water drainage from the new roof is then completed and any finishing touches that may be required such as painting the frameworks, doors, and windows are carried out to complete your home extension.

You can rest assured that there will always be someone to talk to throughout the building process of your new home extension who will answer any questions and make sure that any concerns you have are addressed promptly.



We use timber cultivated under sustainable forrestry guidelines.


Planning Permission

Most home extensions will require planning permission and building regulations approval. Your local council is responsible for granting these. Be aware that different councils have different views, so it is a good idea to have an early discussion with the planning department at your local council to see what they will and what they will not allow you to build. You can save yourself a lot of time and trouble by doing so.

Planning and Design

It is important to bear in mind the current 'look and feel' of your existing property when deciding on the design of a home extension. It is always best to try to match the style of roof as well as the types of windows and doors with those of your existing property, using similar materials wherever possible to ensure that your new home extension will blend in perfectly with your existing property.

Think about your neighbours

During the planning application process, your neighbours will be able to air any reservations or misgivings they may have about your proposed home extension, so it is always a good idea to ensure that your home extension will blend in with the other properties adjacent to you. Talking to your neighbours during the initial stages of the design process can sometimes save you a lot of time and money later on if they have any objections or concerns. Even if you are entitled to make changes they oppose, it might be better to reach a compromise than make life-long enemies.

Hiring the Services of an Architect

You should visit an architect for advice on what can and can't be achieved within the space you have available for a home extension, once you tell him/her what you want to achieve with your home extension. A good architect will also be able to advise you on planning permission, pointing out any local factors that may impact on the design of your home extension and draw up detailed building plans and specifications. Many architects offer to oversee the building of the extension as project manager, for an additional cost, but beware of this tactic as they are trying to steal the job that rightly belongs to the builder you choose to build your extension for you and can never carry out this function better than the builder you choose to build your home extension for you who knows his workers and also the building regulations. By doing so, you can avoid unnecessary tensions that might arise between your builder and your architect, who is not a builder when all is said and done.

Planning Permission

In most cases, planning permission is necessary before any work can commence on your home extension. The planning department at your local council controls the way that neighbourhoods are developed, the way that any available land is utilised, the appearance of home extensions, landscaping, road access and the impact that any new development will have on the environment as well as the neighbourhood.

You will need to apply for planning permission if:

• Your proposed home extension is higher than the highest part of your existing roof
• Your proposed home extension is over 4 metres high and within 2 metres of the boundaries of your property
• The area covered by your proposed home extension will use up more than half free ground available
• The volume of your proposed home extension will be more than 115 cubic metres (length x breadth x height)
• Your home extension will increase the volume of your property by more than 10% (or 50 cubic metres, whichever is greater)

The Planning Process

Your plans will be placed on the Planning Register for public viewing and your neighbours will be notified by your local council. A committee will then make a decision or appoint a senior planning officer to make the decision. This process can take up to 8 weeks, and if you are granted planning permission the planned building works must be completed within 5 years.

If planning permission is declined by your local council, your plans should be modified, taking into account any issues raised by the council, and then resubmitted to the council within 12 months free of charge. Appeals can be lodged so long as they are lodged within 3 months of the council's decision.

A Note of Caution!

People who fail to apply for planning permission before building a home extension can face heavy fines and also be required to demolish any building work.


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For complete Planning Application Guidance Notes click here.

For more video on making a planning application and to make a planning application online visit the the Government PLANNING PORTAL.

More information about obtaining planning permission and the forms to do so can be obtained from your local council local. Most good architects will offer to take care your planning application as well as any appeals/amendments found necessary for an additional fee. Alternatively, you can seek the services of a planning consultant, or simply put in the application yourself. Do remember ask about the extra charges for submitting your planning application.


Building Regulations

Unless your home extension is a porch, conservatory or a detached garage constructed at ground level, taking up less than 30 square metres of floor space, it will be necessary to ensure that everything complies with the Government's Building Regulations.

Building regulations set the minimum standards for the design and construction of buildings (including extensions) to ensure that they comply with the current health and safety regulations. They are also certain requirements in connection with fuel and power conservation.

We shall ensure that your home extension meets all the Building Regulations that may apply to the work we've undertaken, and in making sure that any inspections required are completed and that our work meets the construction and performance standards set by the regulations.

Building Regulations - How to Comply

You or your architect must submit full and detailed plans of your proposed home extension, together with the appropriate application form and fee, to your Local Planning Authority in order to achieve compliance with Building Regulations.

Building control surveyors will then examine your plans to ensure that they comply with current Building Regulations, and if they do, will approve your home extension. We are required to notify the council when work on the building of your home extension commences and at various stages of building your home extension so that inspections can be made to ensure that the laying of the foundations, damp proofing and drainage is carried out to standard. A final inspection will be made upon completion of your home extension, and a certificate of completion issued to you providing everything conforms.


In some cases, you will be able to apply to the local authority for a relaxation to, or dispensation from a certain regulation if you believe that it is inapplicable to your extension. Your application must be made within 28 days of notification of failure to comply with Building Regulations and, if they refuse your applications, you have the right to appeal to the Office of the Deputy Prime Minister.


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Based in North London, House Extensions North London cover the following areas in North London: Enfield, Finchley, Golders Green, Gerards Cross, Islington, Langley, Northwood, Rickmansworth, Slough, and Watford.

Tel. 020 8357 0654 | 0787 804 7975 | 0770 889 7559 | Email:

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