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Verified Pro

Haas Home Extensions Group

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Offers services in KNEBWORTH
Welcome to Haas Extension Group, where we take pride in being the premier suppliers, installers, and design consultants of...
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Loft & Build

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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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Aesthetic Gardens & Drives

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Offers services in KNEBWORTH
Here at Aesthetic Gardens & Drives we specialize in transforming outdoor spaces into stunning landscapes. With a commitmen...

Recent Builder Enquiries

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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06 Jan

Conversion | Loft

Waltham Cross - EN7

Enquiry from: Bukurie H

Start Date: Immediate

customer made an enquiry for loft conversion and confirmed on the local quotes site they would like quotes from a builder.mrs lives in the waltham cross area and would like a call to discuss options.s...

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06 Jan

House Extensions

Waltham Cross - EN7

Enquiry from: Bukurie H

Start Date: Immediate

customer in waltham cross area has requested that we arrange quotes for their house extension project.mrs are considering various options and would like to discuss with a builder directly.please call ...

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02 Oct

Insulation | Cavity Wall

Barnet - EN4

Enquiry from: James M

Start Date: Immediate

customer in the barnet area made an enquiry a couple of projects including cavity wall insulation.call anytime and arrange an appointment to discuss. below is some details about this project: are you ...

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18 Apr

Conversion | Loft

Radlett - WD7

Enquiry from: Elaine G

Start Date: Immediate

Flat or prefab roof dormer window to existing loft.

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22 Jan

Insulation | Cavity Wall

Barnet - EN5

Enquiry from: Bhavesh P

Start Date: Immediate

Cavity wall insulation - beads

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21 Oct

Building work | General

Potters Bar - EN6

Enquiry from: Jay S

Start Date: Immediate

Catnic Lintel CG90/100 - 2 GF Beam B2: GF Beam B2: 203X1*** with 300X280X10mm thick MS Plate as spreader 10mm thick Steel plate to be welded along the length at bottom of the beam to cover outer leaf...

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17 Oct

Insulation | External Wall

Barnet - EN5

Enquiry from: DAVID S

Start Date: Immediate

Solid wall external insulation, semi detached bungalow with attic conversion

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21 Sep

Insulation | External Wall

Barnet - EN4

Enquiry from: Kate N

Start Date: Immediate

External wall insulation (not cavity) on one external wall only (side of house).

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18 Sep

Building work | General

Waltham Cross - EN7

Enquiry from: Frank A

Start Date: 1 to 3 months

customer made an enquiry for building maintenance and confirmed on the quotatis site they would like quotes from a builder.mr lives in the waltham cross area and would like a call to discuss options.s...

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11 Jun

Conversion | Loft

St. Albans - AL2

Enquiry from: Claudine S

Start Date: Immediate

a dormer hip to gable added to the attic bedroom already in the property are you the property owner: owner of the property property type: terrace what are you looking to convert the space into: other ...

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26 May

Building Work | Porch

Hemel Hempstead - HP1

Enquiry from: Girish K

Start Date: Immediate

Upvc porch and replacing porch area tiles. The current structure includes canopy and needs to create a covered porch

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28 Mar

Conversion | Loft

Barnet - EN5

Enquiry from: Dinu S

Start Date: Immediate

homeowner loft conversion- no previous quotes please call to appoint

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24 Feb

Driveway Repair

Radlett - WD7

Enquiry from: Shivani T

Start Date: Immediate

Potential reconfiguration of driveway but as a minimum, to fix the slabs of the drive.

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How much do Builder services cost?

How much do Builders cost? Prices for Builders in 2025 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:

£24,739

Builder job Builder cost in 2025
Garage conversion in Knebworth £9,750-£18,450
Loft conversion in Knebworth £18,750-£28,750
House extensions in Knebworth £29,000-£62,667
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 £2,250-£3,450
Building insurance works in Knebworth £2,250-£3,450
Pebble dashed walls in Knebworth £2,000-£9,200
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 £2,250-£3,450
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 £21,600-£37,400
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

Can an extension add value to my home?

Yes. Most extensions will add substantial value to your home, and you may find that the extension adds more value than it cost. However, it’s important to be sure that the home remains balanced. Extending your garage and leaving your property with no parking spaces, for example, may impact your ability to sell.

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.

Do I need planning permission for external wall insulation?

If you want to install an external wall, it is only wise to consider whether or not a planning permission is required in order to avoid a hefty fine. In a great kudos to the government and a welcome relief to home and property owners, the installation of external wall insulation is seen as an “improvement to the house and not an “extension or an “enlargement. Ultimately, this implies that external wall insulation fitting is to be done under permitted development and a planning application may not be required. However, like many other regulations, there are also exceptions to this rule and the main one is if the activity changes the appearance of your property. Properties such as a listed building having tighter regulations may pose some issues. As a result, we’d advise you to consult your local authority to ensure that there’s no fast rule to this topic before commencement of the external wall insulation project.

At the moment, according to the Government Building Regulations, the surface of the entire wall is to be improved to existing standards if the area to be insulated exceeds 25 percent of the wall. In normal situations this is usually the typical case, however to prevent avoidable fines and other possible punishments, it is always best to reach to your local authority and check out the rules guiding external wall insulation in your constituency. Furthermore, since external wall insulation is not a task that’s recommended to be done by yourself, you can also ask the professional external wall insulation fitting company for the applying rules before proceeding. As a good professional, the company should have a better knowledge of the rules and regulation guiding its activities.

how much value does an extension add to your house?

Are you interested in extending your home to create more living space? If yes, then you’d probably want to know how much value it can add to your property in order to compare the building costs to the potential value gain. Well, as long as you know what you’re doing, your house doesn’t necessarily have to be a money pit. So what are your options when talking about home extensions and what’s the associated value to be gained?

• Bathroom Extensions

Although you should have it in mind that bathroom extensions isn’t usually that cheap, but once done, it can increase the value of a standard UK house within the range of £12,000 to £15,000. Meanwhile the finishing cost of a bathroom can range from £2,500 to £7,000.

• Single or Double Storey Extensions

Single storey extensions are always huge when it comes to increasing the value of your home - giving about 4 to 7 percent increase. If it goes that far, then literally nothing beats a full spectrum, double storey extension which can give up to 11 percent increase in the value of a property - equalling about a whooping £33,000 for a standard home in the UK.

• Conservatory Extension

With conservatories becoming more and more popular in the UK due to the weather conditions, several buyers are now including it’s availability as part of the criteria for purchasing a house. Wonder why? This is simply because everyone wants to enjoy their garden all throughout the year. As a result of this high demand, adding this type of extension to your house can go a long way to increase it’s value. However, it’s very important to incorporate high quality materials during construction. With glass conservatories offering, on the average, up to £5,000 increase in value, the cheaper PVC alternative offers much less value and can also deter potential buyers.

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 long does a loft conversion take?

If you’re about to carry out a loft conversion project, you’d probably be wondering how long it’ll take to complete the task. Well, you’re not alone! This is one of the most common questions when it comes to loft conversion projects, however, providing a set timeframe for completion of such projects is impossible as all loft conversions vary. There are different factors that can determine the duration of your project. These factors include, the materials to be used, the type of the proposed loft conversion, the kind of staircase you’ll like to have installed, the number of windows included, the number of rooms to be added as well as a number of other influencing factors. As a result of these variables, the milestones and timings provided are only to be taken as guidelines. If you’d really like to have a set date, you can get in touch with a professional for help.

Generally, it’ll take up to 8 weeks to complete a loft conversion project.

✓ The first week activities will include putting up scaffolding, receiving the first materials for the build and creating an opening in the roof to gain access to the loft space.

✓ In the second week, the structure of the roof will be ammended and more support added.

✓ Third week, the floor joists will be fitted, building of the loft conversion will start, completion of the external roof works and commencement of plumbing and electric works.

✓ Fourth week, complete the building, construct the loft floor, fit the roof windows, insulation, ventilation and internal stud walls.

✓ Fifth week, apply plaster and plasterboard to the room walls, create a staircase opening and fit the new staircase.

✓ Sixth week, plaster the staircase area, complete plumbing and electrical works, hang the doors, fit skirting, handrails and bannisters and start decoration.

✓ Seventh week, complete the decoration and clean and wipe out all wastes.

✓ Eight week, complete all the remaining tasks.

how to insulate a loft roof?

Insulating your loft roof comes with a wide range of benefits. Not only do you get to maintain a comfortable temperature in your house for longer, but you’ll also get to cut down on your heating bills. If you wish to insulate your loft roof, you’ve come to the right place! This process can be very tedious and time consuming especially if you don’t what you’re doing or lack the required confidence to pull it off. It’s advisable to hire the services of a reputable professional who can guarantee the best results for help and also save you some time and money that can come from potentially costly errors.

 

Before you start rolling out, you’d have to make sure that all cracks, gaps and holes in the ceiling are filled with either a standard filler or decorators caulk. You can also clean between between the gaps in the joists thoroughly. And finally, check for hazards that can cause you problems before getting stated.

  • Remember to leave ventilation gaps as you start from the eaves. Then work towards the loft’s centre, starting from the point furthest from the hatch.
  • Lay the first layer between the joists which should be 100 mm and then the subsequent layer should be 170 mm to make it up to the recommended 270 mm.
  • Carry the electric cables above the insulation and work around visible light fittings.
  • Cut the roll in the centre of the floor when rolling out from the eaves on both sides with the help of a craft knife. Ensure that there are no gaps between the insulation and the joists’ edges.
  • Lag pipes as you go in order to prevent walking over the insulation to get back to them.
  • Ensure that the loft is totally insulated
  • Insulate the hatch.
Can my loft be converted?

Many types of loft are suitable for a loft conversion. In general, you will need at least 2.3 metres of headroom in your existing loft. This is to make sure there is enough headroom after the conversion. Speak to a conversion specialist about the probability and possibility of doing this in your house.

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