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Verified ProOver 20 Reviews

CRS Contractors

20 review(s)
Offers services in KNEBWORTH
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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Rankins Roofing & Building are a family established business with over 30 years in the building/roofing industry. We pride...
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Loft & Build

0 review(s)
Offers services in KNEBWORTH
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 KNEBWORTH
Coastal Prime Ltd provides expert home insulation services across the UK, helping homeowners enhance energy efficiency and...
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Welcome to Home Counties, our team handle projects large and small from residential to commercial. Our Driveway service...

Recent Builder Enquiries

20 May

Conversion | Loft

Knebworth - SG3

Enquiry from: Chris M

Start Date: Immediate

Customer made an enquiry for Loft Conversion via one of our websites. Looking at various options they would like to discuss directly Confirmed interest Please call to discuss and arrange appointment t...

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02 Oct

Building work | Bricklaying

Knebworth - SG3

Enquiry from: Steve P

Start Date: Immediate

rebuild retaining wall of front drive are you the property owner: owner of the property property type: semi detached how much work would you say needs to be done: medium job do you require the brick...

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13 Sep

Insulation | Loft / Roof

Knebworth - SG3

Enquiry from: Steve H

Start Date: Immediate

I have a 3-bed detached house in Knebworth, with loft insulation of 100mm depth and no cavity wall insulation. The property will be empty on 17th Oct. while I find a new tenant and I am looking to im...

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29 Nov

House Extensions

Knebworth - SG3

Enquiry from: Joanne R

Start Date: Less than one month

Hi, We are in the process ofbuying a property in Knebworth and are looking at prices for a double story extension to the side of the house, we would like to create a master en-suite bedroom upstairs a...

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04 May

Conversion | Loft

Knebworth - SG3

Enquiry from: Chris M

Start Date: Immediate

loft conversion bedroom with ensuite Are you the property owner: Owner of the property Property Type: Detached What are you looking to convert the space into: Bedroom/s Are you looking to have stair...

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02 May

Insulation | Loft / Roof

Knebworth - SG3

Enquiry from: J

Start Date: Immediate

Attic insulation

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22 Jul

Building work | General

Knebworth - SG3

Enquiry from: J

Start Date: Immediate

Home owner Customers description : I have a problem with my soakaway. I am looking for my shared down pipe to be capped and for a new soakaway to be constructed in my back garden. The guttering to th...

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14 Jan

Insulation | Cavity Wall

Knebworth - SG3

Enquiry from: Colin P

Start Date: Immediate

Homeowner Supplied and fitted Please contact to appoint

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18 May

Driveway Repair

Barnet - EN5

Enquiry from: Kaveh K

Start Date: Immediate

drive way repair: surface 1m x 1.5 meter - already concreted underneath we need you to get a mix as close as possible to the original and lay it down for us , of course we know it wont be the perfect...

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08 May

Driveway Repair

Barnet - EN5

Enquiry from: Kaveh K

Start Date: Immediate

drive way repair: surface 1m x 1.5 meter - already concreted underneath we need you to get a mix as close as possible to the original and lay it down for us , of course we know it wont be the perfect...

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24 Nov

Building work | Bricklaying

Barnet - EN5

Enquiry from: Padma K

Start Date: Immediate

Air bricks need putting in on outside wall

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05 Nov

Conversion | Loft

St. Albans - AL2

Enquiry from: Iqbal A

Start Date: Immediate

Customer made an enquiry for Loft Conversion via one of our websites. Looking at various options they would like to discuss directly Confirmed interest Please call to discuss and arrange appointment t...

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26 Oct

Conversion | Loft

St. Albans - AL1

Enquiry from: Hazem A

Start Date: Immediate

Customer is looking for quotes for Loft Conversion from pros around St. Albans. Please call to arrange appointment to discuss

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29 Sep

Conversion | Garage

Barnet - EN4

Enquiry from: ANDREW S

Start Date: Immediate

i would appreciate a home visit on 16 or 17 october 2025 4pm if possible so i can discuss my requirements further and then obtain a detailed quotation. i am seeking a cost-effective solution; i curren...

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28 Sep

Conversion | Loft

St. Albans - AL2

Enquiry from: Lucy G

Start Date: Immediate

Customer is looking for quotes for Loft Conversion from pros around St. Albans. Please call to arrange appointment to discuss

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26 Sep

House Extensions

Hatfield - AL9

Enquiry from: Tony R

Start Date: Immediate

Customer in Hatfield area made an enquiry for House Extension online. Please call to arrange an appointment to discuss options

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18 Aug

Conversion | Loft

St. Albans - AL1

Enquiry from: Shahzaib A

Start Date: Immediate

we live in an 2 bed mid-terrace house and are considering a velux conversion for our loft. the floor area is 7.1 x 3.3m and we are planning on using the room as a spare bedroom/study. we have neighbou...

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29 Jun

Building work | Sound Proofing

Barnet - EN4

Enquiry from: Monika A

Start Date: Immediate

Sound insulation in one medium sized bedroom wall

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12 Jun

Driveway Repair

Waltham Cross - EN8

Enquiry from: Andy F

Start Date: Immediate

cement around concrete slabs need renewing

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12 Mar

House Extensions | Single Storey

Borehamwood - WD6

Enquiry from: Jabeen B

Start Date: Immediate

Single storey Extension cost

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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 Knebworth is:

£25,173

Builder job Builder cost in 2026
Garage conversion in Knebworth £9,834-£19,634
Loft conversion in Knebworth £21,875-£41,875
House extensions in Knebworth £29,250-£62,000
Loft insulation in Knebworth £450-£690
Upvc or wood porch in Knebworth £2,625-£4,025
Barn conversions in Knebworth £112,500-£172,500
Basement renovation in Knebworth £30,000-£46,000
Bedroom fitting in Knebworth £1,500-£2,300
Bricklayers in Knebworth £300-£460
Cavity wall insulation in Knebworth £400-£820
Commercial new builds in Knebworth £105,000-£161,000
Conservatory base in Knebworth £675-£1,035
Building maintenance in Knebworth £1,400-£4,225
Building insurance works in Knebworth £1,400-£4,225
Pebble dashed walls in Knebworth £1,275-£7,100
Plasterboard dry lining in Knebworth £638-£978
Residential new builds in Knebworth £105,000-£161,000
Restoration and refurbishment in Knebworth £37,500-£57,500
Roof insulation in Knebworth £7,500-£11,500
Underpinning in Knebworth £1,400-£4,225
Wall cladding in Knebworth £1,125-£1,725
Wall rendering in Knebworth £3,750-£5,750
Demolition in Knebworth £2,440-£3,660
Roof room in Knebworth £15,000-£23,000
Shop refurbishment in Knebworth £3,750-£5,750
Single storey house extension in Knebworth £24,400-£44,934
Soundproofing in Knebworth £900-£1,380
Driveway repair in Knebworth £607-£51,140
Garden room in Knebworth £6,400-£9,600
External wall insulation in Knebworth £6,000-£15,000

Related Builder searches in Knebworth

Builder FAQs

when do you need planning permission for a house extension?

If you’re planning on adding a house extension to your property, you’d probably be worried about whether or not your proposed extension would require a planing permission. Well, it may be relieving to know that not every house extension project would require a formal consent, and in fact, several extensions are covered by the permitted development rights. Not only can this save you a considerable amount of time especially at the project’s planning phase, but it’ll also save you money on the application fee. In the UK, single storey extensions to the house’s rear can be 3 metres deep for both semi detached houses and terraces or 8 metres deep for detached homes.

So how do you know when you’d require a planning permission for your home extension? Well, if your extension plan fits these criteria explained below, then your project is most likely going to be allowable as a permitted development.

• Extensions, which includes previous additions, must not go beyond half of the original house’s total surrounding land area.

• The main elevation, or side elevation where it fronts the highway, must not be extended forward.

• For single storeys, the rear additions must not extend more than the original house’s rear by more than 3 metres in both semi attached homes and terraces (4 metres for detached houses).

• Extensions to the side must be a single storey with a height not exceeding 4 metres and not going beyond 50% of the original house’s width.

• Extensions hat within 2 metres of a boundary should have a eaves height not more than 3 metres.

• Multi storey addition must not extend beyond the original house’s rear wall by a maximum of 3 metres or 7 metres of the boundary opposite the rear wall.

• Permitted development rights do not apply in listed buildings or designated areas.

how does loft insulation work?

A lot of an uninsulated property’s heat is lost through the roof and that’s even more alarming, when you realize this figure is up to a quarter of the total heat of the house. Hence, the tremendous importance of preventing this heat loss through loft insulation which will go a long way to help you against spending unnecessary thousands of pounds on heating bill as well as energy loss.

 

Loft insulation is an effective method to achieve the desired result, however the question is, how exactly does it work? Well, it’s time to find out!

 

Using either a fireplace or central heating to heat up your home, a large quantity of that heat would be lost through the roof of your home. Generally, heat rises and when it does, there’s simply no way to prevent it - it’s just science. Escaping by both the conduction and convection methods via your roof, the heat escaping through your ceiling, into the loft space and out into the open air outside can only be significantly reduced by laying loft insulation.

 

Generally, the added layer of insulation works by trapping the heat inside the room below the loft so as to enable the air within your house to stay warmer for longer. What’s more? The layer of insulation also keeps cold air from the outside from entering your home. As a result, you don’t have to heat your home as much in order to achieve the same temperature for each individual room. Over time, just by doing this you can potentially save hundreds pounds. Getting it installed in your home may actually seem a bit expensive at first, but it’s something that’ll eventually pay off.

How to convert a basement into an apartment?

In some cases, it’s possible to convert a basement into an apartment. This can be a great way to incorporate an additional dwelling into your property and increase its value. However, converting a basement into an apartment can be quite expensive and time-consuming.

As with any type of dwelling, you’ll need to think about basic things like access, damp proofing, ventilation, insulation, heating, electrics, plumbing, lighting and décor. If you’re planning on extending your basement, then you’ll also need to ensure that your property is sufficiently supported.

It’s a good idea to consult a professional, like a basement conversion building specialist, to find out how feasible your project is before you go ahead with it.

Are barn conversions a good investment?

A barn conversion can be a great investment for lots of reasons. When done well, barn conversions can be great at holding their value, meaning you could sell yours for a great price. They can also look fantastic, often with period features coupled with large areas of glazing. This can make them a great place to live, especially if you enjoy being in the countryside.

However, barn conversions do have their disadvantages. They may require extensive renovation work to bring their energy efficiency levels up to standard, which can be very expensive. It’s also important to be aware of their location – they might be on a working farm or close to several other converted buildings.

It’s essential to get a survey conducted before you buy a barn you plan to convert. This can tell you about any structural problems it might have and give you an indication of whether you might be able to get permission to convert it. You can also buy barns with planning permission already in place.

how to underpin a house

The importance of underpinning a house cannot be overemphasized. Firstly, what is underpinning? Well, underpinning is simply the act of reinforcing, repairing, strengthening or improving the depth of an existing foundation by lowering the footing to ensure that it rests more on more reliable and supportive soil. Not only does this method help to strengthen your building and preserve its structural integrity, but it also does increase your property’s value and gives you peace of mind knowing your property is safe. If you’re thinking about underpinning your house, you have two options – do it yourself or call in a reputable structural engineer. The latter is more advisable as the method involves a lot of specialized knowledge, skills and tools to guarantee a successful outcome. In this post, we’re going to take you through the process involved in underpinning a house. Let’s take a look!

To get started, you should know that concrete underpinning features excavating pier footings around the building at about 2 to 3 metres distance between each other. In some cases, underpins can be installed from within the house. The footings of the underpin should go very deep into the underlying soil in such a way that fully supports the weight of the building or structure. Once done, now proceed to attaching the new footing to the building. You can achieve this by excavating underneath the existing footing to make for a stronger prop. Individual prop and pier arrangement is then strengthened using strong steel bars. Once completed, the concrete is then poured.

A professional underpinning contractor will make sure there’s sufficient space left between the existing footings and the new underpins as this space will ensure that the new underpins can be easily used to jack up the house and level it once the poured concrete cures.

how much does a kitchen extension cost?

Being the most used room in a house, it’s little surprise kitchen extension are usually one of the most popular requests in the UK. They do not only open up a frequently used space in your home, but also goes a long way to add value to your property. However, to know the value that’ll added you must first determine the cost of building such an extension before moving forward. Generally, a typical kitchen extension will cost within the range of £20,000 to about £50,000 plus VAT, based on the size of your project as well as your location.

In reality, a single accurate cost of a kitchen extension will vary depending on a lot of influencing factors, one of which is the type of the extension. Let’s take a look!

✓ Rear extension. You may want to consider this type, if you do not have sufficient space for a side return. This will extend your kitchen into your garden which implies that you’re going to give up some green space to make this a reality. The average price to have this done in London will be about £30,000 or more including VAT, and about £20,000 plus VAT or more in other areas.

✓ Side return extension. This, normally, isn’t a huge add to your property, but will create a lot of space for your kitchen while also be a lot reasonable in terms of cost. This type will extend your home into an alleyway at the side of your property if any is available there. On average, the cost of the side return extension should be about £50,000 plus VAT in London and a lot less in the other regions.

how to build a garden room?

With homeowners now a lot more unwilling to move or make any costly extensions due to the uncertainty that lies ahead in the property market of the UK, a garden building which represents a cheaper alternative seems to be the best option available. Not only is it one of the most affordable ways to add space to your home while staying within your budget, but it’s also one of the best ways to add immense value to your property as more and more potential home investors are now seeking properties with an outdoor garden room. They’re the perfect investment for those looking to expand their space without having to carry out huge extension projects which normally consumes both time and money.

Garden rooms are best built by professionals to guarantee the best results. However, if you feel confident enough to undertake the project, then this guide will give you an idea of the process.

✓ Build the foundation. Here you can build the foundation using concrete, but in cases whereby there are root systems closeby then you can make use of low impact screw piles.

✓ Start the construction process with timber frame, SIP panels as well as other modular components and materials

✓ Once you’re done with the construction process, the next course of action will be to develop and position the roof structure on to the top of the newly constructed garden room. Here, you can also decide to use sun pipe and solar heating or PV panels. You can also protect the construction from the elements by making use of cedar cladding.

✓ Doors installation. The best type of doors to use here are draught sealed doors which can also be treated hardwood or powder coated aluminium .

✓ Make the finishing touches here and there and make sure all connections are complete.

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.

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