How Much Does A House Extension Cost In St Albans

The Only Guide You Need For Home Extension Costs in St Albans

Posted by Craig | Updated May, 2024 | 10 Min Read Time

At a glance 

  • On average, home extensions in St Albans cost between £2000-£2500 per square metre, but as discussed above, some factors can change this.

In this article, you’ll find the following:

    • An explanation of several factors that can influence the cost of a house extension 
    • Types of cost-effective extensions in St Albans
House extension projects are exciting but can be nerve-racking when unsure of the costs involved.
This article will help you understand and break down the costs involved in such a project. Whether you are looking at a single, double or wrap-around home extension, a rough estimation can always be achieved.
We can provide you with a completely free no obligation quote for your new project. 
A double story side extension in St Albans we built

On average, home extensions in St Albans cost between £2000-£2500 per square metre, but as discussed above, some factors can change this.

Are you considering adding extra space to your home in St Albans?

1. Factors Influencing House Extension Costs in St Albans

Several factors can affect the cost of your house extension, but here are the main ones:
Size: The more extensive your extension is, the more the price will increase as more materials and labour are needed.
Type: The simple extensions are usually smaller and more cost-effective.
Materials used: This part can make a difference in your extension build; customers can easily spend an extra 50k here.
Location: Some central St Albans locations require extra planning, which can increase the price.
Modern complex designs: Though these new home extensions can look very visually pleasing, they come with a hefty price tag.

2. Cost Breakdown of Home Extensions in St Albans

On average, home extensions in St Albans cost between £2000-£2500 per square metre, but as discussed above, some factors can change this.
Your money will be spent in multiple project areas and can be broken down roughly into the following areas.
– Foundation: 15-20% of the total cost.
– Structure: 25-30% of the total cost.
– Roofing: 10-15% of the total cost.
– Windows and Doors: 10-15% of the total cost.
– Internal Finishing: 20-25% of the total cost.
– Miscellaneous (e.g., permits + planning permission): 5-10% of the total cost.

3. Hidden Costs to Consider for House Extensions in St Albans

Ground floor kitchen extension in st albans
There are some costs involved that can often be overlooked when planning your home extension. Although many of these costs can’t be avoided, they can certainly be controlled and reduced.
– Architect Fees: 7-15% of the project cost. This is an unavoidable project cost, but we work with highly experienced and cost-effective architects.
– Planning Permission: These fees will vary based on the size and complexity of your extension.
– Utilities: When you implement a home extension, the plumbing and electrical services will often need to be moved, which comes at a cost.
– Contingency: Set aside 10-15% of your budget for unexpected expenses.

4. Tips for Cost-Effective Single and Double-Storey House Extensions in St Albans

Here are some of our top tips to keep the costs in check for your new home extension in St Albans. Understanding the single storey extension cost upfront can help you budget effectively and avoid unexpected expenses, ensuring that your project remains within financial boundaries.
Plan Carefully: Use an experienced architect and builder to design and plan your home extension. Any mistakes in this stage of the build can be hugely costly later down the road. Familiarizing yourself with the cost of a single-story extension early on can inform your planning and design decisions, helping to ensure that your project aligns with your budget from the outset.
– Quality vs. Budget: Although one quote might be more expensive than another one you have received, often there is a good reason for this. Everyone has heard the saying you buy cheap… you buy twice.
– Energy Efficiency: Investing in insulation and energy-efficient features for your home is smart. They can save you money in the long term and reduce your home extension costs.
PHOTO 2022 11 15 20 47 10 6

5. Conclusion: How Much Exactly Does A Home Extension Cost In St Albans?

While we know that home extension costs can vary widely, understanding the factors involved and budgeting for expenses is essential.
Careful planning with industry professionals can help you achieve your dream home within budget.
Costs break down
Extension – £2000-£2500 per square metre.
Architect & Planning – 7-15% of the project cost.
Utilities – £500-£2500
Contingency – Be sure to have 10% of your budget left for that, just in case moment.
Thanks for reading our blog; if you have any questions, don’t hesitate to contact us. We will be more than happy to help you.
If you found this post useful and know someone else who would benefit from it, please share it with them.

If you are still interested in finding out more about house extensions consider reading our blog on >> Where to start with house extensions 


Craig Smith

The founder of CJ Smiths Construction Company for over 14+ years and a proud citizen of St Albans City.

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