How long will my House Extension take?

By the time most of us realise we need a house extension, we really need a house extension.

Maybe your child has already outgrown the small front bedroom, or your teenager has started to hog the family bathroom in the morning? Lock-down may have also exacerbated space issues for us that were only on the periphery of our mind beforehand! Whatever our particular circumstances, once we have decided we definitely need to extend we don’t want to be waiting forever to make our extension a reality!

Getting the relevant permissions for your house extension requires time and planning, so guidance from an expert is a necessity. There are some essential processes and permissions that need to take place BEFORE you start to build. House Architects have outlined these below to give you an idea of the minimum timescales involved to obtain your permissions before a spade goes in the ground!

1. First thing’s first, Design.

The first stage of the process involves getting a measured survey of your house done so that your architect can explore the design options with you. Once you have a design decided upon, you can then get some quotes from builders to see how much your design will cost.

The design process is so important as it helps you to have confidence that the design you’re going with isn’t just what is easiest for a builder to construct, but it’s what you want. It is as useful for discounting unworkable or bad ideas, as it is for discovering new and unexpected solutions for your home.

The Design stage helps you to really be clear on what you want, and find out if its feasible, by allowing you to get prices from builders.

The Measured Survey and Design Consultation process with House has an average turnaround time of 3 weeks. Getting quotes from builders take on average 3-6 weeks, depending on how busy your builder is. So to summarise, this stage can take on average 6-10 weeks, or 1 and a half to 2 and a half months.

2. Planning Permission

Your House Architect will be able to advise you at a free initial consultation whether or not you require planning permission for what you want to do to your home. Some extensions may fall within the permitted development criteria.

Obtaining planning permission should come after you have finalised the design, usually done at a Pride Road Concept Design Workshop.

The planning stage starts with an architectural technician coming out to your property to conduct a full measured survey. You should then allow up to 4 weeks for the production of the drawings on CAD. Once the drawings are finalised and approved by you they are ready to submit to your local authority. The local authority will take 10 days to validate the application and then 8 weeks to process it. Some councils caveat their validation letters saying that the decision may take longer than 8 weeks so bear this in mind when planning ahead! If the planners ask for any design changes or further information during this 8 week period then an extension of time is often required for amending and submitting drawings and the planners consideration of them.

So, what’s roughly the total minimum timescale for gaining planning permission? From survey to decision you’re looking at a realistic minimum of 14 weeks, or 3 and a half months.

2. Building Regulations.

The other approval you need is Building Regulations Approval. This is needed even if you’re not making external changes to your property as the main concern of the building officer is health and safety and checking that the proposals comply with the current legislation for building.

In terms of timescales, you should allow up to 4 weeks for the architect to produce the drawings package and then, once submitted, the timescales for building regulations approval can vary drastically depending on who you appoint as the building officer. If you go to your local council they will usually say allow 8 weeks for a decision (but, once again, this can take longer). If you go to an approved inspector, who are an independent company separate from the council, then they will ususally be able to give a decision more quickly, some say up to 3 weeks (and in some cases, in our experience, it can be even quicker than this).

So what is the minimum timescale for building regulations approval from start to finish? From production of drawings to decision notice you should factor in a minimum of 7 weeks, or about 2 months.

This takes the total timeline of gaining permissions to a total minimum of about 5 and a half months.

There is a way to make the process quicker, however, by running the planning and building regulations applications concurrently. There is a risk in doing this that if there are significant changes required by the planners then there will be some abortive costs in changing the building regulations drawings too. However if the project is not considered contentious and time is of the essence then it’s something you should certainly consider as it can reduce the total 5 and a half month (minimum) process to 3 and a half months.

If you want more information on how long your project will take to build click here.

To book a free initial consultation or a workshop with  Pride Road Liverpool South click here.

written by Catherine Traynor

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