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Verified ProOver 50 Reviews

Colt Property Improvement

74 review(s)
Offers services in HARPENDEN
We are a family orientated company established in 1994. Utilising only the best quality materials and a highly skilled wo...
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Loft & Build

0 review(s)
Offers services in HARPENDEN
We can cover all aspects of a loft conversion and extensions. If you require, we can also design the project including dr...
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Coastal Prime

0 review(s)
Offers services in HARPENDEN
Coastal Prime Ltd provides expert home insulation services across the UK, helping homeowners enhance energy efficiency and...
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Local Roofing Consultants

0 review(s)
Offers services in HARPENDEN
Ring for free survey our quotes on budget on time .we offer insurance backed guarantees members of confederation of roofin...
Verified ProOver 10 Reviews
Welcome to Home Counties, our team handle projects large and small from residential to commercial. Our Driveway service...

Recent Builder Enquiries

09 Mar

House Extensions | Single Storey

Harpenden - AL5

Enquiry from: Aleem K

Start Date: Immediate

two storey rear extension, single storey front and rear extensions, first floor front extension, rendering and alterations to openings, part garage conversion, porch and complete internal redecoration...

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05 Sep

Building Work | Porch

Harpenden - AL5

Enquiry from: Daryl B

Start Date: Immediate

Looking to create a porch area on our terraced property. Porch to contain a small coat rack and boiler. Work needed to completed asap.

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11 Feb

Conversion | Loft

Harpenden - AL5

Enquiry from: Stoycho I

Start Date: Immediate

hello, i am looking for specialists for a shell loft conversion / dorma on a terraced house. the project is based in harpenden. it is a three bedroom house, built in 1960s. the whole loft space is 44...

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03 Dec

Conversion | Loft

Harpenden - AL5

Enquiry from: Michael M

Start Date: Immediate

loft conversion for 12 stewart road *** please arrange site visit and provide proposal are you the property owner: owner of the property property type: semi detached what are you looking to convert t...

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17 Nov

Insulation | Cavity Wall

Harpenden - AL5

Enquiry from: Simon S

Start Date: Immediate

cavity wall insulation in a detached chalet bungalow. are you the property owner: owner of the property property type: detached how many bedrooms do you have: 1-2 property age: 1930-70 are you in a c...

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06 Oct

Driveway Repair

Harpenden - AL5

Enquiry from: Gerard v

Start Date: Immediate

repair of the existing crossover which has been badly damaged during building works.

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26 Jul

House Extensions

Harpenden - AL5

Enquiry from: Rosie D

Start Date: Immediate

*homeowner house extension please call to appoint

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21 Mar

Conversion | Garage

Harpenden - AL5

Enquiry from: Kenny M

Start Date: Immediate

a single garage conversion to a professionally converted standard, ideally with bathroom are you the property owner: relative of owner do you have a: single garage what will the space be used for: li...

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21 Mar

Conversion | Garage

Harpenden - AL5

Enquiry from: Nick A

Start Date: Immediate

adding first floor and flushed windows (front and back) to existing attached garage for office space. currently a void (ie ground floor for parking garage, straight up to roof) are you the property ow...

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16 Dec

Insulation | Loft / Roof

Harpenden - AL5

Enquiry from: Martyn L

Start Date: Immediate

are you the property owner: owner of the property property type: detached how many bedrooms do you have: 3-4 property age: 1970-2000 are you in a conservation area: no are you looking for loft insula...

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15 Dec

Insulation | Cavity Wall

Harpenden - AL5

Enquiry from: Martyn L

Start Date: Immediate

are you the property owner: owner of the property property type: detached how many bedrooms do you have: 3-4 property age: 1970-2000 what is your current source of heating for the renewable incentive...

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01 Oct

Conversion | Garage

Harpenden - AL5

Enquiry from: Christina H

Start Date: Immediate

looking for a quote to convert garage into a home gym. we're already using it as a gym but it's not insulated and needs new gym flooring etc. are you the property owner: owner of the property do you h...

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13 Aug

Conversion | Garage

Harpenden - AL5

Enquiry from: Jane L

Start Date: Immediate

Single garage conversion with no knock through, man hole cover currently in garage is believed to be private property but would need access through any floor laid down over it.

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24 Jan

Building Work | Porch

Harpenden - AL5

Enquiry from: Esra E

Start Date: Immediate

Are you the home owner of that property? YES Are you replacing an existing porch or is this a new build? New Build What material do you require, UPVC? UPVC What colour do you want it to be? White I as...

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18 Apr

New Build | Residential

Harpenden - AL5

Enquiry from: Bob C

Start Date: Immediate

Quote for timber frame house construction please

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10 Apr

Conversion | Loft

Harpenden - AL5

Enquiry from: HENNA J

Start Date: 1 to 3 months

Homeowner Please contact to appoint Are you the property owner: Owner of the property Property Type: Semi detached What are you looking to convert the space into: Bedroom/s Are you looking to have st...

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06 Jun

House Extensions

Harpenden - AL5

Enquiry from: Winston P

Start Date: Immediate

Build above garage to create 4th bedroom + en suite; move current family bathroom and refit; redecorate upstairs Are you the property owner: Owner of the property Property Type: Detached Looking For: ...

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06 Jun

House Extensions | Single Storey

Harpenden - AL5

Enquiry from: Winston P

Start Date: Immediate

Customer is currently in the process of looking for quotes to add a Single storey extension to their property. Are you the property owner: Owner of the property Property Type: Detached Looking For: Si...

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01 Mar

Conversion | Loft

Harpenden - AL5

Enquiry from: Tim B

Start Date: 1 to 3 months

Existing loft space converted into extra bedroom with en suite Are you the property owner: Owner of the property Property Type: Semi detached What are you looking to convert the space into: Bedroom/s ...

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18 Feb

Building work | Wall Rendering

Harpenden - AL5

Enquiry from: Jes C

Start Date: 1 to 3 months

External rendering to match existing mottled rendering.

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How much do Builder services cost?

How much do Builders cost? Prices for Builders in 2026 can fluctuate relying on the sort of work that you need to have carried out in your residence.

Are you planning to erect a new house or structure? If yes, then you’d probably want to know just how much it’ll take to get the project over the line to help you set a budget and start to plan. Building a new house is requires huge financial investment and as a result, there’s the need to carry out your due diligence before you proceed. In this post, we’re going to give you an insight into the prices charged by builders to erect a new home or structure.

First and foremost, like every other home project, the price charged by builders to construct a new house or structure depends on a wide range of factors. These factors include the size, location, accessibility as well as qualifications of the builders you wish to employ just to mention a few. For instance, you’d expect the cost of building two-storey in London to be a lot more expensive than the price of a one-story building in Scotland. However, we’ll try our best to give you an idea of the price range you can expect to incur to complete your project.
In general, a builder will charge within the range of £10 to about £15 per hour on the average. For small building projects which includes wall and foundations repairs, a builder will typically charge about £11 per hour. However, the price charge will depend on the extent of the job due to the fact that simple tasks such as repointing only costs about £10 per hour, while laying new foundations can cost up to £15 per hour.

The table shows the types of work that Builders typically do and the average cost range of these tasks. Some tasks take longer to finish than others so prices do fluctuate by job.

View our Builder cost guide View our Builder advice

The average price
of a Builder in Harpenden is:

£24,239

Builder job Builder cost in 2026
Garage conversion in Harpenden £9,834-£19,634
Loft conversion in Harpenden £21,875-£41,875
House extensions in Harpenden £29,250-£62,000
Loft insulation in Harpenden £300-£3,714
Upvc or wood porch in Harpenden £2,625-£4,025
Barn conversions in Harpenden £112,500-£172,500
Basement renovation in Harpenden £30,000-£46,000
Bedroom fitting in Harpenden £1,500-£2,300
Bricklayers in Harpenden £300-£460
Cavity wall insulation in Harpenden £325-£5,410
Commercial new builds in Harpenden £105,000-£161,000
Conservatory base in Harpenden £675-£1,035
Building maintenance in Harpenden £2,250-£3,450
Building insurance works in Harpenden £2,250-£3,450
Pebble dashed walls in Harpenden £2,000-£9,200
Plasterboard dry lining in Harpenden £638-£978
Residential new builds in Harpenden £105,000-£161,000
Restoration and refurbishment in Harpenden £37,500-£57,500
Roof insulation in Harpenden £3,875-£10,750
Underpinning in Harpenden £2,250-£3,450
Wall cladding in Harpenden £1,125-£1,725
Wall rendering in Harpenden £3,750-£5,750
Cero insulation in Harpenden £250-£10,000
Insulation scheme (hhrco) in Harpenden £250-£10,000
Demolition in Harpenden £2,440-£3,660
Roof room in Harpenden £15,000-£23,000
Shop refurbishment in Harpenden £3,750-£5,750
Single storey house extension in Harpenden £24,400-£44,934
Soundproofing in Harpenden £575-£25,690
Driveway repair in Harpenden £607-£51,140
Garden room in Harpenden £6,400-£9,600
External wall insulation in Harpenden £2,250-£10,000

Related Builder searches in Harpenden

Builder FAQs

how much does a two storey house extension cost?

If you’re considering adding a two storey house extension, then setting a budget for this project would be a great way to get started. Similar to a rear extension, a two storey extension usually leaves the rest of the building needing some work and, due to its size, this may imply the re-development of the entire house - which is why they can be very costly. Some of the other influencing factors that can have big impact on a two storey house extension cost includes: your location, the size of the build, complexity of the design ( anything beyond the standard build will normally require more expertise and time), the glazing to be incorporated ( the more the glass used in the project, the more the material cost), as well as the team used.

Generally, when it comes to extensions, the major part of the expenses will be made on the build of the project. This is because it doesn’t only cover the material cost but also the contractor’s overhead as well as the daily rates. At this stage, the extension prices can be determined by the standard of the work that’s being done.

For a fairly average room size of about 18 square metre, the two storey extension should cost within the range of £2,500 to £3,000 per square metre - with the range being determined by the finishes incorporated. Therefore, a two storey extension of about 18 square metre should cost within the range of £45,000 to £55,000. However, this is with the assumption that there are standard window sizes, bathroom suits are modest, and without any need for any purpose joinery or glazing. If you wish to include all these extra features you’ll also have to pay more to make the total cost between £70,000 to £80,000.

how much to re render a house?

Rendering of a house is one of those projects that can greatly improve the visual appeal of your home, enhance it’s energy efficiency, protect the brickwork from the elements and ultimately, add value to your home. Generally, the cost of rendering a house normally costs within the range of £25 to £70 per metre square, while the average cost house rendering costs stands at about £40 per square metre. Therefore, a 3 bedroom semi detached house will cost within the range of £4000 to about £5000.

The total cost of rendering a house is determined by a wide range of factors. These factors includes the following:

✓ Type of the rendering. There are three main types of rendering which includes sand and cement rendering, monocouche rendering as well as acrylic or silicone rendering. However, re-rendering applies to sand and cement sooner and it’ll also have to be painted every 3 to 6 years. Consequently, longer term cost can be higher when compared to the other types.

✓ Ease of access. Where your contractor will have to work around obstacles like shrubs or conservatory, this can make the cost a bit higher as it’ll take longer time to complete.

✓ Prep work. If the contractor needs to fill some cracks or perhaps an old mortar requires tuck pointing before rendering can be started, this will also affect the cost.

✓ Scaffolding. In the event whereby the job requires the use of scaffolding and you’ll have to hire one as a different cost, then the price will be higher.

✓ Your location. Due to the high standards of living and higher demands in areas like London or the Southeast, prices in these regions are usually higher than that of the other regions like Midlands and North.

What types of work does a builder do?

Any residential building work requires a general builder. The term Residential building work means any work which is involved in building a house or changing or adding to a home. It also comprises of mending, refurbishing, ornamenting or applying shielding treatment to home. A dwelling is defined as a building or a part where people live. This might include an apartment, house or a townhouse.

Here is a list of some of the works that require a building licence:

• construction of a garage, carport or a shed

• renovation for bathroom, kitchen or laundry

• structural landscaping and building swimming pools

• construction of conservatories and atriums

• house lifting for example, raising the height of an existing structure permanently

• removing and resitting dwellings

• steam rooms and saunas.

General building contracts might also involve work that needs a specialist. These works can be appropriately subcontracted. However, this work must be carried out by the container of a permitted contractor licence or competent administrator certificate in that specialist category.

There are a number of different categories of licences that are available depending on whether you want to oversee the work or have an agreement with another party. When you have a contractor licence, you will have the option of submitting a contact to bid on the work. You can only do the categories of work designated on your licence card. Contractor licences can be allotted to people and businesses and partnerships.

With a certificate of a qualified supervisor, you will be able to supervise the type of work specified in the certificate. Such certificates are only issued to individuals and do not allow you to contract for work.

The licence of an endorsed contractor is issued to those individuals who have applied for a contractor licence but also possess the necessary qualifications and experience to become a qualified supervisor.

What is a barn conversion?

A barn conversion is where an agricultural building is altered to serve a different purpose. Lots of barns conversion projects involve converting an old barn into one or more homes. However, barns can also be converted into other types of commercial building, like offices.

how much is a loft conversion?

With the ability to add approximately one third of your existing living space ( by converting your old, unused attic) to your home or property without having to let go of your garden, it’s quite easy to see the reason why loft conversion has rapidly grown to become one of the most popular home improvements in the UK. However some homeowners usually shy away from the idea simply by looking at the perceived high cost of carrying out such a project, despite several researches showing that loft conversions offers the best rate of return on initial investment when compared to the other home improvement projects. So exactly how much would it cost to carry out this project?

Just like several other home improvement projects, the cost of a loft conversion varies greatly depending on a wide range of influencing factors. These factors include the size of your home, how old your home is as well as the quality of the fixtures and fittings you want to install. For instance, a high end bathtub alone can cost you thousands of pounds, meanwhile you can also construct a full bathroom suite on just a couple of hundred pounds. However, to give you an idea of the minimum cost of a loft project we’ll look at the most popular types and the minimum cost of each.

✓ Internal Loft Conversion - The most affordable type of loft conversion tends to start from £25,000 and above.

✓ Dormer or L-Shaped Dormer Loft Conversion. These are the most popular types of loft conversion. Dormer price tends to start from £35,000, while the L-shaped dormer starts from £45,000.

✓ Mansard Loft Conversion - This involves replacing the entire side of a sloping roof with a vertical wall and flat roof. It requires a planning permission. The type of loft conversion usually starts from £45,000.

✓ Hip To Gable Loft Conversion - This usually starts from £50,000.

do you need planning permission for a loft conversion?

Typically, loft conversions do not require planning permission except in certain situations. They’re usually covered under what’s known as Permitted Development. Certain building works like loft conversion, rear extension and conservatories are granted planning permission by local authorities. Permitted Development, however, gives you a free range to improve your home without having any issues from the councils or regulations. Before your planned loft conversion can be covered under Permitted Development, there are some certain criteria that must be met. This criteria includes the following:

✓ The extension must not go beyond the existing slope of the roof at the front of the house.

✓ The loft space converted must not go beyond 40 cubic metres in a terraced house.

✓ The roof’s height must not be increased by the extension.

✓ The loft space converted must not reach beyond 50 cubic metres in a detached or semi detached house.

✓ The plan for the extension mustn’t involve structures like balconies, verandas or anything other structures of this nature.

✓ The roof extension should be positioned as far back as possible or at least 20cm from the existing eaves.

✓ The side that faces the window openings should be at least 1.7m beyond the floor and the windows should also be obscured.

✓ The roof extension must not overhang the existing roof or wall of the house.

✓ The materials that are to be used must be similar or the same to the materials that has already been used on the house’s exterior.

However, you should bear in mind that there are some properties that are exempt from Permitted Development. Examples of these type of properties include conservation areas, Areas Of Outstanding Natural Beauty and World Heritage sites. Permitted Development does not also provide coverage for listed buildings.

Can a mortgage include renovation costs?

In a nutshell, a mortgage loan is for the acquisition of an asset, so lenders won’t tend to give you anything else in a mortgage that is going to cover your home renovation costs. When you are applying for your mortgage, your provider will examine the price of your new household. For example, if you’re planning to buy a property for £200,000, but you need another £50,000 to help improve it, you’ll find that your lender might turn you down.

Essentially, with any mortgage loans that you take out on your possessions, the bank or creditor theoretically owns your home till you’ve entirely paid off your loan, which is why it is very unlikely that you will get extra funds from them. There are some mortgage providers who will be willing to add on some building costs, but it is entirely up to you whether to choose it or not.

With most mortgages, banks and other lenders will usually give you a maximum of 95% of what you purchased your property for. That means, that even if you contemplate the household has the probability to be valued at so much more, you’ll have to find an alternative way of paying for the developments you have in attention. So, if the accumulation of extra funds on to your mortgage loan is out of the question, you’ll need to find additional ways of paying for the home developments.

It is well and good if you have the cash saved up, or else, you can explore other payment options which your bank or lender may be able to help you with. There are several methods by which you can collect the cost to pay for the improvements, from personal loans to credit cards or even overdrafts, there are tons of ways to lending money. Keep in mind these are all forms of debt so keep an eye out for the interest rates when you are repaying.

how much do roof rooms cost?

How Much Do Roof Rooms Cost?

The price of your roof room may vary depending on your location within the country. Other factors that can also play a key role in determining the price of a roof room includes the conversion’s type as well as the legal and technical issues it’s currently facing. Usually, the cost of roof rooms will range between £1,200 to £2,000 per square metre. The differences in the price per square metre is influenced by the size of the alterations to the roof, the type of roof room to be constructed, the access, location as well as the finishing type.

• DORMER LOFT CONVERSION.

Here, one of the slopes of a pitched roof is substituted for a box-shaped structure. The outcome is a flat roof space which enables the fitting of full sized windows as well as the incorporation of several appliances. This is quite expensive as it involves a total rebuilding of one roof pitch alongside the complete internal works that are associated. The average cost of a standard dormer loft project will range between £25,000 to £50,000.

• HIP TO GABLE LOFT CONVERSION

Here a vertical brick wall is used to substitute the roof’s slope at the ending part of the terrace on detached buildings. The average cost of this type of roof room will range between £32,000 to £60,000.

• ROOFLIGHT LOFT CONVERSION

This basically involves fitting rooflight windows in the roof. Other improvements include flooring, plasterboarding, strengthening of the existing floor, as well as installation of rooflights. The average cost of this type of roof room will range between £15,000 to £25,000.

• MANSARD LOFT EXTENSION

This roof room can create an extra storey on top of an existing building as it makes a space featuring two or four external walls that are a bit sloped. The average cost of this type of roof room will range between £40,000 to £70,000.

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