Please use the calculator below to calculate the cost of your building work.

Calculate the cost of your extension.

A basic builder's estimate would be based around £1,100-£1,500 per m2 this would include plant, labour and material, which would be to a builders finish. 

What will your Extension cost? (guide price only) 
The best way to work out the cost of your extension, is to figure out the floor area, which is the length multiplied by the width, use the calculator on the left to help you. once you have your area, multiply that by £1,100.00 then multiply that by VAT at 20%, then add them figures together that will give you a final figure.

For example: 
A 5m x 5m extension.
The floor area will be 5 x 5 = 25m2 
X £1,100.00 = £27,500.00
X 20% VAT = £5,500.00
Add those figures together 
£27,500.00 + £5,500.00 = £33,000.00

This would be a rough guide price for the cost of your extension, there are lots of factors to take into account, e.g. foundation type, brick type, roof type and different quality finishes. 

That cost would include:

• Free accessible CCTV coverage.
• Free professionally cleaned driveway.
• Foundations 1.3m x 0.6m – Piled or deeper foundation price may change.
• Block and beam floor / concrete slab.
• Screed finish to match existing levels. 
• Supply and fit of new pitched/ flat roof. 
• New fascias and soffits. 
• New gutter runs & downpipes. 
• The supply or fitting of stud walls. 
• Plaster finish to walls and ceilings.
• Radiators. 
• Electrics: double sockets, light switches, pendant/ downlights, extractor fan.
• Supply and fitting of new internal doors to new extension. 
• Supply and fitting of new skirting and architraves.
• Supply of scaffolding, skips & Temporary toilet.
8 Year Warranty.

Please take into consideration- You may require additional items, such as fitted kitchen / Bathroom, Velux windows, bi-folds, steel beams, additional electrics, etc.
if you do then this will be added onto your guide price.

In our quote if you do not have an electrical drawings, we will pass your drawings onto our qualified electrician who will decide how many electrical fittings you may need, you can add or deduct any electrical socket you want.

If you would like us to give you a free fixed quote for your building works, please
phone or email us on 01268 416040 or

We would require a set of drawings. If you do not have drawings, we would require a free site visit to view and discuss the works which you want carried out.  

Once we have had a site visit, we will then pass your information onto our estimating team, who will write up a detailed fixed quote meeting all of your requirements.

All of our building work will be carried out in accordance with building control regulations.
Upon completion of works, all building materials and debris will be removed from site and disposed of.

All of our jobs can be covered by accessible CCTV coverage this is to enhance both your safety and security of the building. This system will remain with you after the project has finished completely free of charge, extra cameras can be added at cost value.

How to find the right builder for your project? The success to any building project is your builder. 
But anyone in a van can offer a building service, so it is so important you do your research first, when it comes to choosing the right builder for you, as there are a lot of cowboy builders out there. 
Please check with your local authority building control team, and ask them questions about your builder. The building control team will generally know most building companies in your region as they oversee the projects. 
Here are a few tips in choosing the right builder for you:
1. It is important that the builder comes with good references, however the best builders should be booked up weeks or months in advance. 
2. Local recommendations are usually best, so follow up recommendations from your family, friends, neighbours and local architects.
3. Visit sites like Trustatrader, Federation of master builders to check the company out and view their recent feedback.
4. Make sure they have been up and running for a while by going on the government website, Click Here 
5. Ask for references for previous work, view the previous work and see what the customers have to say about the work they carried out. 
6. Check that the builder is insured for risks to persons and property, and ask for a copy of the certificate
7.Check out how the payments will work, never pay any upfront costs.
8.Check to see if you get a guarantee with your building works.

Comparing Quotes

When it comes to comparing quotes, you should always check you are getting what you have asked for and what is required on your drawings, check for any hidden extras. Don’t automatically go for the cheapest option. 

1. We would recommend getting at least three written quotes (not estimates). Get those quotes broken down the best you can so you can see what you are paying for. 

2. Check exactly what is included in the quote, for example does it include scaffolding, skip hire etc.

3. Check that VAT is included in the Quote.

5. Check what payments you will be making, never pay any upfront costs! -Our payments are invoiced, once each stage has been completed, and passed by the local authority- building control.

We do offer a Design & Build Package which includes planning and building regulation drawings as well as carrying out the building project. We carry out all the above in house by our own designers and architects, which makes the process run smoothly right through to the building works and completion, making it less stressful for the client. 

We also offer 3D Visuals...

All of our drawings are drawn up using a CAD system, so they are easy to read and understand by the client and the craftsmen. 
Please fill in the form below to apply for planning or building regulation drawings, and we will get back to you as soon as we can. 

If you need Help Finding A Local Architect Or Structural Engineer, click on the link below. if you would like us to recommend one please do not hesitate to Contact Us .

Will you need planning permission? Click Here To Visit The Planning Portal 

Apply for a competitive estimate or any advice you may require.

Please Visit us on the following sites by clicking on the images:
We would recommend reading this guide, before you choose your builder.

Contact us today.

Phone: 07545307419
Office: 01268 416040

Business Hours

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Cleanliness: 5.0 out of 5
Value: 5.0 out of 5
Punctuality: 5.0 out of 5
Quality: 5.0 out of 5
Overall opinion: 5.0 out of 5
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"Loft extension - Fantastic. Paul Bailey has done work for me, my family and friends over the last 15-20 years. Reliable, prompt. Very good."
"I would not hesitate to recommend Paul. The management of the whole project was exceptional. Paul is very approachable, professional and well organised."
"I would not hesitate to recommend Paul Bailey Constructions, The quality of work, punctuality of workers and friendliness was exceptional."
"Have already recommended to friends who have booked Paul for work on their extensions. Excellent workmanship"
"Amazing finish, organised and clean build, very pleased I would Extremely recommended!"
"Very reliable, good aftercare too. Very honest and trustworthy."
"Extension. Happy and satisfied with work and result. Would highly recommend."
"Reliable and friendly. Really pleased with work and result. I am going to use him for more work. Have recommended to family and friends."
"Kitchen and extension done. Excellent. always on time. Explains everything. Very trustworthy. No hesitation to recommend."
"Huge Project- Refurbishment and extension. Happy and satisfied. Really pleased with the quality if work, which is great. Good ideas and suggestions."

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