Considering an extension?

Considering an extension but don’t  know where to start?

Extending your home is a great way to make space, save money and maximise the  return on your property. The key is in the planning. Carefully considering every detail will save so much stress, time and money later down the line. Plans should be in  place for everything from windows and doors to light switches and decorative details. 

Not only will this make it a level playing field to compare quotes but it will also ensure that everyone is on the same page and there’s less room for stressful  hasty decisions, errors  or adjustments  further  down the line. 

Permitted Development & Conservation 

A single storey extension up to four metres for a detached house and three metres for a semi detached  can be carried out under permitted development (A lawful development certificate can  be obtained to validate this).  Otherwise a full planning application would be needed. 

A pre application meeting with the local planning department is a good starting point to determine what is and isn’t acceptable to the local authorities. 

For a listed building the first thing would be to complete a conservation survey.This is to ensure that no harm is being done to the building or to  the history of it. 

In conservation areas there are often restrictions on the size and scope of the development.  It would be a good idea to check what has been granted to others in the area and make sure to work closely with local councils to get the best outcome possible!


Boundary Walls & Party Agreements 

A party wall ( a wall shared with a neighbour) agreement is needed if a boundary wall or  excavation within 6 metres of the boundary wall. 

Open communication about plans with all of those affected and a written agreement is required prior to works being started. 

Depending on the local authority boundary walls can only be added or changed to certain heights and certain angles that do not interfere with the light or view of the neighbouring properties. 

Lofts & Garden Rooms 

A great way to add space to a home is to go up into the roof. However loft extensions do require scaffolding, staircases and  party wall agreements where as a garden room is much simpler to install and therefore also worth considering. 

Plans  & Drawings

Architectural  drawings are essential. Consideration must be given to the positioning of the doors,  windows (the bigger the better) elevations and external materials. 

A structural engineer will determine how the extension will be structured and how the rest of the building will be safely supported. Costs will need to be calculated here for steel and materials. Careful consideration should be given to what materials are used and where. 

A flat or gabled roof? Timber of brick frame? Glazing and lighting considerations. All of this will need to comply with building regulations. Careful consideration needs to be given to the thermal performance. This includes distribution of glass and heating (solar and ground sourcing)

An electrical plan right  down to the kitchen and bathroom layouts are essential here and will all determine the cost of the build. 

Budgeting & Costs 

Once there are clear plans in place its possible to go out to tender. Post covid, Brexit and more recent events with oil prices and  transportation issues materials have gone up hugely and many companies are now only providing estimated material costs because the prices are changing so quickly. This makes it harder to budget.

We would always recommend allowing 20% on top of estimates in case costs run over or better materials are chosen than were specified.

Building Projects are exciting and the end results are so rewarding but the secret to success is in the planning.  Carefully considered extensions will bring you  space, light comfort and joy. Extending your home will allow you to maximise the efficiency in your home and create a space that is tailored to the way you want to live. The key is in the planning. 

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