You probably don’t want to hear this but the question, “how long is a piece of string?” is apropos for the subject title of this blog. However, if you bear with us, you will find the information below helpful along the way and we even give some guideline pricing at the bottom. You can cheat and skip to the bottom now if you wish.
A house extension project on your or anybody’s home will have four elements.
1. Design, Supervision & Certification
This involves taking your requirements (brief) from concept to detail design. Once the design is completed, construction drawings are completed and work commences on site (after planning permission is obtained when required). Oversight and supervision are critical to ensuring your project is realised and done in compliance with planning, quality and Building Regulations. On completion, after snags, the project is signed off and certs are provided. The certs are essential to protect the value of your existing property and the new work completed. Typically, this part of the work is 10% of the overall cost.
2. Structural Alterations & Demolitions
Any substantial re-ordering and upgrading of the existing house involves a lot of alterations and oftentimes the demolition of old, badly designed and poor-quality buildings (e.g. conservatories, old extensions or outbuildings). Structural openings are where new openings are formed and support of existing walls and roofs has to be designed into the solution. We use a lot of steel beams and posts in our projects so new openings can be formed and light brought back into dark, dim spaces. Every project is different, but this work can be anywhere from 10-20% of the cost.
3. Renovation of the existing space
Where we started with this blog is especially relevant here. Renovation can involve as little as the removal of a set of double doors and replastering on the back wall of the house (unfortunately rare) to a whole house deep renovation. Deep renovation involves reworking the fabric of the building to improve its energy performance and creating new, beautiful finishes. Because clients are committed to improving the overall performance and comfort of the existing house, the renovation is becoming a larger piece of the project. Costs for this element are rarely below 20% and can be as high as 40-50%.
4. New Extension
We finally get to the house extension itself. For us in Shomera, this is the icing on the cake (and maybe the cherry on top too). It is what really transforms our clients’ homes. The extension is not only new space, but it also rejuvenates and opens up the existing space in the house. You are permitted 40 SQM under exempted development. However, a lot of the time, through imaginative use of the existing house and well-thought-out integration of new and old, our clients get what they are looking for with 20-30 SQM of added living space. The cost for this element is generally 40-60% of the overall cost.
In Summary
We finally get to the house extension itself. For us in Shomera, this is the icing on the cake (and maybe the cherry on top too). It is what really transforms our clients’ homes. The extension is not only new space, but it also rejuvenates and opens up the existing space in the house. You are permitted 40 SQM under exempted development. However, a lot of the time, through imaginative use of the existing house and well-thought-out integration of new and old, our clients get what they are looking for with 20-30 SQM of added living space. The cost for this element is generally 40-60% of the overall cost.
