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Hilson Roofing

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Offers services in HARROW
Your friends in High Places We cover all aspects of roofing from minor repairs to full design and install We are quali...
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CRS Contractors

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Offers services in HARROW
we Are a family run business with over 30 years experience built on reputation Our services include all types of roofing...
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Loft & Build

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Offers services in HARROW
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

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Offers services in HARROW
Coastal Prime Ltd provides expert home insulation services across the UK, helping homeowners enhance energy efficiency and...
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We are a professional, multi-disciplinary property construction and refurbishment company providing a comprehensive range ...
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Ring for free survey our quotes on budget on time .we offer insurance backed guarantees members of confederation of roofin...

Recent Builder Enquiries

15 Oct

Building Maintenance

London - NW2

Enquiry from: Block R

Start Date: Immediate

External wall insulation Lead

Air conditioning, building maintenance, gas boiler replacement

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07 Oct

Wall Cladding

Morden - SM4

Enquiry from: Tushar T

Start Date: Immediate

Repair loose composite cladding that has come away from the wall. Needs fixing back securely

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29 Sep

Loft Conversion

London - SW16

Enquiry from: Katherine S

Start Date: Immediate

Need a set of stairs up to attic full install. would like the stairs to be the right size and height that would allow the attic to act as a second bedroom

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22 Sep

Basement Conversion

London - E5

Enquiry from: David G

Start Date: 1 to 3 months

Like full basement works

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31 Aug

Wall Rendering

London - W5

Enquiry from: Daniel O

Start Date: Immediate

External rendering of the whole house

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30 Aug

Loft & Roof Insulation

Staines-upon-Thames - TW19

Enquiry from: John I

Start Date: Immediate

Problem with damp mould in bedrooms coming from the loft after damage from squirrels/rats. I need it checking & repairing

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24 Aug

Sound Proofing

London - SW12

Enquiry from: Anne T

Start Date: Immediate

External wall insulation Lead

Acoustic insulation around pipes running from upstairs bathroom in box in downstairs bedroom

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14 Aug

House Extension

London - N21

Enquiry from: Saeed Y

Start Date: Immediate

Loft conversion side and rear extension

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12 Aug

Basement Conversion

Surbiton - KT5

Enquiry from: Luke L

Start Date: Immediate

Addition of a staircase, and make the cellar dry (not damp) so it can be used for storage

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03 Aug

Building Maintenance

London - NW11

Enquiry from: Becky B

Start Date: Immediate

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03 Aug

Building Maintenance

Edgware - HA8

Enquiry from: Donna H

Start Date: Immediate

I need someone who cam remove mould

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28 Jul

Building Maintenance

London - NW11

Enquiry from: Becky B

Start Date: Immediate

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28 Jul

Building Maintenance

Potters Bar - EN6

Enquiry from: Vishal R

Start Date: Immediate

External wall insulation Lead External wall insulation Lead External wall insulation Lead External wall insulation Lead

Repair cracks in walls of from porch caused by extreme heat

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05 Nov

Loft Conversion

Harrow - HA3

Enquiry from: Viju U

Start Date: Immediate

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30 Aug

Garage Conversion

Harrow - HA2

Enquiry from: Hashim H

Start Date: Immediate

I want to convert a semi-detached garage into a study room. The garage roof is removed (no roof at the moment)

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28 May

Porches

Harrow - HA3

Enquiry from: Rasik V

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 vbuild. what material do you require, upvc? - unsure. what colour do you want it to b

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28 May

Wall Cladding

Harrow - HA2

Enquiry from: Kieran C

Start Date: Immediate

Upvc wall cladding to front of house

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07 Mar

Garage Conversion

Harrow - HA2

Enquiry from: Shanth K

Start Date: Immediate

I want to covert my garage into studio

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23 Jan

House Extension

Harrow - HA1

Enquiry from: Mahmood K

Start Date: Immediate

Flat roof kitchen extension at rear. Labour only builder required. All my material

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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 Harrow is:

£25,007

Builder job Builder cost in 2026
Garage conversion in Harrow £9,834-£19,634
Loft conversion in Harrow £29,688-£64,688
House extensions in Harrow £32,000-£73,000
Loft insulation in Harrow £350-£5,345
Upvc or wood porch in Harrow £2,625-£4,025
Barn conversions in Harrow £112,500-£172,500
Basement renovation in Harrow £30,000-£46,000
Bedroom fitting in Harrow £1,500-£2,300
Bricklayers in Harrow £300-£460
Cavity wall insulation in Harrow £325-£5,410
Commercial new builds in Harrow £105,000-£161,000
Conservatory base in Harrow £675-£1,035
Building maintenance in Harrow £2,250-£3,450
Building insurance works in Harrow £2,250-£3,450
Pebble dashed walls in Harrow £2,000-£9,200
Plasterboard dry lining in Harrow £638-£978
Residential new builds in Harrow £105,000-£161,000
Restoration and refurbishment in Harrow £37,500-£57,500
Roof insulation in Harrow £3,875-£10,750
Underpinning in Harrow £2,250-£3,450
Wall cladding in Harrow £1,125-£1,725
Wall rendering in Harrow £3,750-£5,750
Cero insulation in Harrow £250-£10,000
Insulation scheme (hhrco) in Harrow £250-£10,000
Demolition in Harrow £2,440-£3,660
Roof room in Harrow £15,000-£23,000
Shop refurbishment in Harrow £3,750-£5,750
Single storey house extension in Harrow £24,400-£44,934
Soundproofing in Harrow £575-£25,690
Driveway repair in Harrow £607-£51,140
Garden room in Harrow £6,400-£9,600
External wall insulation in Harrow £3,125-£12,500

Related Builder searches in Harrow

Builder FAQs

how to repair a patio?

A patio is an outdoor space which can be used for a variety of stuffs which includes fun time with family and friends, reading time or just relaxing as the fresh breeze blows. With all these benefits and more, it’s becomes more obvious that there’s a need to keep your patio in a tip top condition at all times. If otherwise, you may not be able to enjoy your patio to your satisfaction and probably, for as long as you would want. You simply have to provide it with a regular maintenance which involves inspecting and identifying the damages that needs to be repaired before it gets out of hand. Fortunately, the minor repairs can be done by yourself if you’re confident enough. However, for bigger damages it’s advisable to call in a professional for help. In this article, we’ll take you through the patio reparation process.

✓ Prepare the area. This involves removing the problem piece gently and carefully. If there’s a piece you think can still be useful, store it in the re-use pile or you can start a new one. Once you’re done removing the pieces, the next thing to do would be to start removing anything that’s unwanted from the damaged area like debris, unwanted soil etc, and start sand fitting with some fresh sand. This should be levelled out to ensure there’s no bumps.

✓ With the sand down, you can start by putting the pieces back in together. This should be done gently to avoid any further damage. Do this until your patio

✓

What types of extension are there?

There are many different types of extension. For example, you could install an orangery, flat or pitched roof extension, over-structure extension, single or double storey extension or a glass box extension. Which one of these is most suitable will depend on your existing property.

does a single storey extension add value to your house?

Does A Single Storey Extension Add Value To Your House?

When you’re looking to construct a single storey extension or perhaps you’re just searching for means to increase the value of your property, this question always pops up. The short and simple answer to this question is a resounding yes, a single storey extension can go a long way to increase the value of your property. Just like any other home improvement, when done right, adding a little extra living space is one of the top things you can probably think of that’ll provide a cool increase in your property’s value. However, before you rush in you must also take note of some factors so you can be certain a single storey extension is the right option for you. These factors include the quality of the build, complexity of the build, cost of the build versus the value gain, ceiling price in the area, finance costs as well as the inconveniences and stress.

Generally, the average cost of a single storey extension can range from £34,000 to £37,000. For this price, you should get a standard sized rear or side extension which also includes the cost of a kitchen - it’s the most commonly use for a single story extension especially in the UK. So it’s important to know the value they’ll add to your house before deciding to make such an investment.

The value added to your property will depend largely on the quality and size of your single storey extension. The value is usually calculated by estate agents using the number of bedrooms, bathrooms as well as the floor area. Inside London, it’ll typically be priced at £5,000 to £10,000 per square metre, while outside London should be within the range of £900 to £2,000 per square metre.

when is underpinning required

If you’re currently experiencing some structural issues with your building or property and you’ve heard a thing or two about the several benefits associated with getting underpinning done, you may be wondering if underpinning might just be the answer to your worries. Well, one thing you should when it comes to underpinning is the fact that, while there are some structural issues that may actually warrant an underpinning job, there are also some situations that can not be fixed by underpinning. In this post, we’re going to consider the events whereby underpinning of your house will be required. Let’s take a look!

First and foremost, you should know that underpinning isn’t required for issues related to slab heave. Footing movements which are likely to reverse normally occur when the content of the soil moisture changes unevenly which gives rise to slab heave. This movement results for a reversible effect.

Generally, underpinning is done to remedy problems related with the movement of the footings of a building or property, but as stated above – not all movements require underpinning. So, when is underpinning required? More often than not, a situation that’s resolved by underpinning is the event whereby the footings of a building or structure drops or subside as a result of some reasons that are irreversible. For example, footing movements caused by a footing set on a soft or loose soil which may be irreversible.

In the event whereby the footings of your house haven’t been installed as deep as required during the initial construction, then you will need to have your building underpinned to make it more stable. If you’re also looking to increase the load on your foundation like adding another storey, you may also need to have your house underpinned to support the extra weight added.

how thick should render be on external wall?

Render serves two basic functions. One is it’s protective qualities as render acts as waterproof for the wall which enables them breathe by allowing water vapour move from the inside to the outside of the structure while also working to prevent water or rain from finding its way inside the structure. While the second function is the decorative qualities as render is able to provide the structure with a fine finish and colour to make the building a lot more appealing and correcting faults in line and level in the masonry.

If you wish to apply render on your external wall, you’d probably be wondering just how thick the render should be to perfectly serve both of functions. In this article, we’re going to take a look at just that!

For a render thickness, the British Standard Wind Driven Rain Index has come up with 4 ratings which include Sheltered, Moderate, Severe as well as Very Severe. An area with Very Severe rating include South West England. This rating implies that the thickness of the render in this area should be increased to at least 20mm for a direct one coat render applications as well as 5 to 6 external wall insulation base coat applications. And if you happen to reside within one mile of the coast, it’s strongly recommended you incorporate an extra repellent protection like Paraguard AG from Parex.

In general, render that’s prepared on site with cement and sand should be have a minimum of 20mm to 25mm thickness. Although, it should be noted that the quality of the render is based on quality of the sand incorporated, the design mix as well as being largely dependent on how good the mixing technique from the applicator is. The most common reasons why traditional renders fails is due to both poor mixing ratios and low quality materials used.

Is a basement conversion worth it?

Whether a basement is worth converting depends on your location and how much work it requires.

A basement conversion can be a great way to add space to your home, and can raise your property value. However, it can also be one of the most expensive ways to do this, so if there’s a possibility to extend your property, or convert a loft or garage, it’s worth considering this first.

You should also compare how much your basement conversion will cost with the amount it could raise your property value by. In some areas, a quality basement conversion could earn you money in the long run, but in others it’ll only cost you. If you’re planning on staying in your property for a long time this might not matter to you, but if it’s not your forever home then it’s an important thing to think about.

What cement should I use for bricklaying?

Cement is a crucial element in bricklaying that’s widely used in both construction as well as finishing works. Generally, they’re used to aerate concrete blocks, connect bricks, prepare plaster, floor levelling as well as the making of precast products. The major reason cement is one of the most common construction materials as its incredible ability to hold structure together. To get a cement plaster, you’d simply have to mix cement with both water and sand. However, when you mix cement with lime, sand and water, you’ll get a mortar.

For cements mortars to be used inside joints, you’ll have to include 1 part cement at the minimum to not more than 2 parts sand by weight which should be dry mixed and moistened with enough water to allow for troweling and packing without falling apart. Generally, the cement sand ratio in a mortar is in between 1:2 to 1:6. The cement and sand mix ratio is largely based on the importance of the project.

Cement provides a plethora of uses in bricklaying and these includes:

• Preparation of cement concrete

• Preparation of cement mortar

• Building fireproof and thermal proof structures

• Building chemical proof structures

• Serving as a grout material

• Building hydrographic and frost resistant structures

• Manufacturing precast members

• Constructing aesthetic concrete

• Constructing cement concrete roads

There are several types of cements with each having its specific purpose. For instance, the type of cement more suited to building a fire proof structure is a high alumnia cement and to build a hydrographic structure, cements like expanding cement, hydrophobic cement, pozzolana cement and quick setting cement are the best bet. Acid resistant cements are more useful in building chemical proof structures, portland cements are best suited to making grout materials, while coloured cements are preferable to building aesthetic structures.

Does cavity wall insulation lead to damp problems?

Insulating a cavity wall should not affect the damp proofing of the wall. All insulation approved for use in cavity walls has been tested to ensure that it does not allow damp to pass through the wall. Some walls which receive a lot of wind driven rain are unsuitable for cavity wall insulation.

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