Renovating a house can be a daunting task and the expense to construct a second level over a single storey extension is often a critical consideration for homeowners.
This financial component can significantly influence not just the design and size of the project but also the materials used and even the construction timeline.
Complicating matters is the reality that there is a wide range of potential costs due to factors such as geography labor rates and individual project specifications.
But what if the costs to build a second storey could result in long-term savings?
How does that impact your decision?
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Average Building Cost For Single Storey Extension
Extending a house by building a single storey extension can be a cost-effective option adds significant living space and offers a cheaper alternative to moving house. An important consideration for such a project is understanding the cost involved.
The costs can range from £1500 to £2400 per square meter. Therefore for a 4m x 5m single storey extension you’d potentially be looking at build costs ranging from £30000 to £58000.
Remember however these figures provide a general guideline. The final costs are greatly dependent on the complexity of the building work quality of materials and finishes used.
Factors such as where you live in the United Kingdom whether you live in a Barratts house and potential issues that may arise can unintentionally inflate costs.
Interior Fit-Out Expenses
In addition to building costs the interior fit-out costs also need to be factored in. Various rooms such as the kitchen bathroom utility room and costs related to flooring and wall finishes all add to your interior fit-out expenses.
A common increase in costs usually comes from aspects like:
- Quality of ceiling finishes
- Electric under-floor heating costs if not using existing central heating system
- Installing bi-fold or sliding doors for natural light
- Adding rooms such as a home office wet room or utility room
Keep in mind the professional fees for services like architect design fees surveryor and project management can also add £12000 or more to the cost not forgeting VAT and Building Control application.
Professional Project Fees
When considering the build on top of a single storey extension you must factor professional project fees. Usually these include an architect design fee and project management fee.
Your architect is responsible for creating construction drawings and getting your planning permission approved. The cost for this service will add up to £12000 or more to your budget.
Additional professional fees may include a structural engineer surveyor or even specialists like an ecology or archaeological report contributor. These professionals are necessary to ensure your extension matches local building regulations and that potential land issues are identified.
Planning Permission Costs For Single Storey Extension
No matter where you are in the United Kingdom obtaining planning permission is paramount before you start any building work.
Planning permission costs for a single storey extension are fixed at £206 in England. However depending on your property and design you may be required to pay for additional reports. Flood risk tree ecology and archaeological reports are commonplace with certain builds and can increase the cost substantially.
Apart from the planning permission other local authority-related costs you may come across include the Building Control application which validates your building regulations approval. The cost here varies depending on the size of the extension you plan on building and can range from £200 to £900.
Another common cost that arises during building an extension is a party wall agreement. If you share a party with a neighbour and your extension requires you to dig closer to their property a party wall settlement might be necessary.
This can increase your overall planning cost by an extra £700 to £1000 per neighbour.
Building Regulation Costs For Single Storey Extension
Building a single storey extension like a dining room home office or an extra bedroom on your house requires adherence to the United Kingdom’s building regulations. These regulations are outlined in a compliance certificate which can be obtained through a Building Control application.
Moreover these rules ensure your extension features appropriate foundations ceiling finishes and meets insulation gap requirements among other standards.
The building regulations approval cost for a ground floor extension like a living room kitchen or a playroom varies from £200 to £900. These costs depend on the extension’s size and complexity.
It’s recommended that homeowners include this amount in their extension contingency fund to avoid surprise costs during the project.
If you’re considering adding on top of your existing single storey extension like a home depot or even a second storey make sure your existing foundations are checked by a suitable engineer and your architect. If your extension plan ends up increasing the footprint or weight of the structure your old foundations may not be appropriate to support this additional weight and may need reinforcement.
Notably reaching out to professionals like Michael Holmes an author for the Real Homes magazine for advice or recommendations will help manage your expectations realistically and ensure your project’s success.
If you are thinking of extension plan during the COVID-19 pandemic or if you live in a more suburban part of the country the costs might even go up due to less competition among contractors or even higher cost of construction materials like lumber and others. Remember a cheaper option isn’t always cost-effective in the long-run.
The compulsory building regulation costs although additionally expensive are just a small part of the total cost you’ll spend extending the house. However these costs ensure both your existing house and its extension adhere to the country’s safety standards in building and construction work.
The regulations also cover eligibility for VAT exemptions a feature that might be useful to many homeowners. Do consult with your builder a building contractor or a structural engineer for professional guidance through the process.
Overall these costs may seem expensive at the beginning but considering options like moving house or starting from scratch extending your existing house could prove a more cost-effective option in the long run.
