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Verified Pro
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

0 review(s)
Offers services in WELWYN
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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Here at Aesthetic Gardens & Drives we specialize in transforming outdoor spaces into stunning landscapes. With a commitmen...
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Keybur Paving

0 review(s)
Offers services in WELWYN
Keybur paving are a trusted, professional company with a great reputation to uphold. We are based in epsom and cover all o...

Recent Builder Enquiries

25 Sep

House Extensions

Welwyn Garden City - AL7

Enquiry from: Halima T

Start Date: Immediate

Customer is looking for House Extension quotes. They are unsure of options so would like to discuss. Confirmed interest via SMS//phone Customer lives in Welwyn Garden City area Please call to arrange...

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17 Aug

Building Work | Porch

Welwyn Garden City - AL7

Enquiry from: Everjoy K

Start Date: Immediate

i would like a quote for an extension. are you the property owner: tenant (with permission) property type: terrace looking for: porch do you have planning permission: yes do you have plans drawn up: n...

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07 Jun

Insulation | Loft / Roof

Welwyn Garden City - AL7

Enquiry from: Janine H

Start Date: Immediate

loft insulation quote on semi detached house are you the property owner: owner of the property property type: semi detached how many bedrooms do you have: 3-4 do you currently have loft insulationn: y...

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14 Aug

House Extensions | Single Storey

Welwyn - AL6

Enquiry from: Kate P

Start Date: Less than one month

customer in the welwyn area made an enquiry a couple of projects including single storey house extension.call anytime and arrange an appointment to discuss. below is some details about this project:cu...

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14 Aug

House Extensions

Welwyn - AL6

Enquiry from: Kate P

Start Date: Less than one month

we would like an extension to be used as a lounge. the area is approx 6m x 4m are you the property owner: owner of the property looking for: single storey extension do you have planning permission: n...

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17 Jan

Insulation | Cavity Wall

Welwyn Garden City - AL7

Enquiry from: Peter W

Start Date: Immediate

quote for cavity wall insulation to mid terrace 1950's property. note there is a single storey upvc conservatory to rear. are you the property owner: owner of the property property type: terrace how ...

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06 Jun

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: David B

Start Date: Immediate

full length dormer and full length velux rear ext cost of both about 8metre are you the property owner: owner of the property property type: semi detached are you looking to have stairs: yes what are ...

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29 May

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: David B

Start Date: Immediate

full length dormer and full length velux rear ext cost of both about 8metre are you the property owner: owner of the property property type: semi detached are you looking to have stairs: yes what are ...

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23 May

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: David B

Start Date: Immediate

full length dormer and full length velux rear ext cost of both about 8metre are you the property owner: owner of the property property type: semi detached are you looking to have stairs: yes what are ...

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13 May

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: David B

Start Date: Immediate

full length dormer and full length velux rear ext cost of both about 8metre are you the property owner: owner of the property property type: semi detached are you looking to have stairs: yes what are ...

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27 Apr

House Extensions

Welwyn Garden City - AL7

Enquiry from: Manuel P

Start Date: Immediate

customer in welwyn garden city areas is looking to do a couple of projects at the moment, and would like quotes for house extension.confirmed interest via email at 27/04/2021 17:59.please call to arra...

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15 Apr

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: Evi P

Start Date: Immediate

I would like to have a full loft conversation to a bedroom and a bathroom. Curtly the loft is fully boarded.

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11 Apr

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: Evi P

Start Date: Immediate

looking for a quote and option for loft conversion 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 look...

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01 Apr

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: Evi P

Start Date: Immediate

looking for a quote and option for loft conversion 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 look...

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06 Nov

Insulation | CERO Free

Welwyn Garden City - AL7

Enquiry from: Mike C

Start Date: Immediate

5 bedroom detached house potentially needs external wall insulated.

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01 Aug

Conversion | Garage

Welwyn - AL6

Enquiry from: Natasha C

Start Date: Immediate

treatment room - plumbing, sink and toilet, door and window fitting, flooring and walls. are you the property owner: relative of owner do you have a: single garage what will the space be used for: ot...

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06 Jul

Building work | General

Welwyn - AL6

Enquiry from: Anita K

Start Date: Immediate

1. Maintenacne of rainwater goods which includes replacement of downpipe, provision of downpipe bracket and securing lose stop ends 2. Re-ponting of brick joints 3. strenthening works to the roof tr...

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22 May

Conversion | Loft

Welwyn Garden City - AL7

Enquiry from: Paul L

Start Date: Immediate

customer visited the myloftconversionprices.co.uk site and submitted an enquiry. property type: detached, property owner: owner, looking to convert into: living space, work description: conversion of...

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03 May

House Extensions

Welwyn - AL6

Enquiry from: Siva G

Start Date: Immediate

are you the property owner: owner have you considered getting your windows replaced to match a new conservatory: no other forms: kitchen design & installation, house extension agreed to receive quote...

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04 Jul

Building work | General

Welwyn Garden City - AL7

Enquiry from: Steven E

Start Date: Immediate

I'm buyinga Euramax Edwardian conservatory 3m deep x 3.8m wide. The ground work and wall will already be done, I just need a professional to erect it Are you the property owner: Tenant (with permiss...

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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 Welwyn is:

£25,829

Builder job Builder cost in 2025
Garage conversion in Welwyn £9,750-£18,450
Loft conversion in Welwyn £39,375-£59,375
House extensions in Welwyn £34,250-£72,000
Loft insulation in Welwyn £450-£690
Upvc or wood porch in Welwyn £2,625-£4,025
Barn conversions in Welwyn £112,500-£172,500
Basement renovation in Welwyn £30,000-£46,000
Bedroom fitting in Welwyn £1,500-£2,300
Bricklayers in Welwyn £300-£460
Cavity wall insulation in Welwyn £400-£820
Commercial new builds in Welwyn £105,000-£161,000
Conservatory base in Welwyn £675-£1,035
Building maintenance in Welwyn £2,250-£3,450
Building insurance works in Welwyn £2,250-£3,450
Pebble dashed walls in Welwyn £2,000-£9,200
Plasterboard dry lining in Welwyn £638-£978
Residential new builds in Welwyn £105,000-£161,000
Restoration and refurbishment in Welwyn £37,500-£57,500
Roof insulation in Welwyn £7,500-£11,500
Underpinning in Welwyn £2,250-£3,450
Wall cladding in Welwyn £1,125-£1,725
Wall rendering in Welwyn £3,750-£5,750
Demolition in Welwyn £2,440-£3,660
Roof room in Welwyn £15,000-£23,000
Shop refurbishment in Welwyn £3,750-£5,750
Single storey house extension in Welwyn £21,600-£37,400
Soundproofing in Welwyn £900-£1,380
Driveway repair in Welwyn £607-£51,140
Garden room in Welwyn £6,400-£9,600
External wall insulation in Welwyn £6,000-£15,000

Related Builder searches in Welwyn

Builder FAQs

Will I need planning permission to convert my loft?

Planning permission is not normally needed for a loft conversion as they are covered by permitted development rights. A conversion company will tell you if you do and help you with this. For more information, see our article about planning permission.

What is a bricklayer?

This is an individual who is trained in the art of working with concrete blocks or bricks, clay bricks as well as other kinds of mortar building materials. In a combination of these materials and good bricklaying skills, a bricklayer can build and repair veneer as well as full brick construction, arches, partitions and other structures.

Contrary to many beliefs, a bricklayer actually does more than laying of bricks. There’s more to being a bricklayer than you can probably think of. A single bricklaying projects requires a wide array of skills. Let’s have a look at these skills!

• Using damp resistant materials to seal foundations.

• Spreading mortar between joints and applying them to serve as a thick layer binding the bricks together in rows.

• Reading and working from specifications as well as plans.

• Working with brick-cutting machines.

• Taking charge and caring for cement blocks or bricks, clay bricks and the likes.

• Construction of scaffolding - subject to possession of some licenses in some states.

A bricklayer mostly works outdoors, in the field and may also work at heights. Depending on the job, a bricklayer can work as part of a team or be in contact with the public. They are mostly recruited by building and construction companies and bricklaying sub contractors. However, they can also set up their own private construction firm or become a self employed tradesperson.

A bricklaying qualification is one of just two construction trades which can continue to become a registered builder. And regardless of the form a bricklaying employment takes, there are certain qualities that makes a really good bricklayer. These includes:

• Ability to work at heights and outdoors

• Enjoy practical work

• Technical aptitude

• Good hand-eye coordination

• Independent and yet a team player too

• Top physical fitness

• Attitude and attendance.

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.

does a kitchen extension add value to your house?

If you’re planning to add a kitchen extension to your property or perhaps you’re simply looking for ways to increase the value of your property, this is one of the common questions that usually pops up. A simple answer to this question is yes, a kitchen extension will add value to your house. With a kitchen being one of the most frequently used room in a house, adding an extra space to the commonly used room can only increase the value of the entire property. However, to determine the value added by such an extension, there’s a need to calculate the cost of setting one up first.

Kitchen extension costs are greatly influenced by a wide range of variables such as the size, type of the extension and specifications, your location, professional fees, materials used and more. Overall, the type of the extension you opt for will play the most significant role in the determination of your kitchen extension cost. Here, we’ll be looking at a single storey kitchen extension.

For a single storey kitchen extension, you can expect your home’s market value to increase within the range of 5 percent to about 10 percent. When trying to calculate the cost of kitchen extension, it’s crucial to take into account how much value it’ll add to your home so as to make sure that the amount expended will not outweigh the expected value to be added by the project.

For a more accurate idea, there’s the need to consult local estate agents. However, for a much needed guideline, single storey kitchen extensions are usually able to add about 5 to 10 percent to a home’s value, while double storey extension should be up to 20 percent. But as stated earlier, this will depend on several variables.

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.

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

Is Planning Permission needed for Sound Proofing?

In general, you won’t need planning permission to install soundproofing. If you are installing soundproofing against a shared wall, you will usually need to follow the rules and restrictions set out in the Party Wall Act. In listed buildings and conservation areas, there may be extra restrictions on soundproofing.

How to dot and dab plasterboard?

How To Dot And Dab A Plasterboard

If you want a fast and simple way to achieve a smooth and sturdy wall which is decoration-ready, then dot and dab plasterboard is the way to go! It’s a relative simple process but can also be a bit challenging. Therefore, if you lack the necessary training or experience, hiring a professional would be a great step to protect your investment and guarantee the best results. Here, we’ll provide you with a deep insight into the plasterboard’s dot and dab procedures. Let’s have a look!

• At the thickness of the board with the adhesive, mark the ceiling and floor as well as the wall to indicate the centre of each board.

• Ensure the wall’s height is 15mm more than the plasterboard

• Make a mixture of the adhesive and achieve a thick consistency. Apply a consistent layer of the mixture around the wall’s perimeter, edge of the ceiling and any other openings with the use of a trowel.

• Select dabs that are about 250mm long and 50mm to 75mm wide and apply the adhesive in them. Make use of 3 vertical rows for individual boards. Also ensure to apply, at skirting level, a band of adhesive.

• Position the board’s reverse side against the dabs, and laying against the packers. Then make the board align with the ceiling and floor marks with the help of a straight edge.

• Raise the board till its tight against the ceiling with a board lifter. Once done, use the plasterboard to wedge the board into place before you remove the board lifter.

• Repeat the same process for the remaining parts of the room. Once completed, make sure the adhesive is set before you remove the boards.

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