Domestic Buildings

ATJ Building & Groundworks offer a full range of building services in and around the Northamptonshire area, including Milton Keynes, Bedford, Wellingborough, Kettering and Daventry. Choosing the right building company or tradesmen can be a difficult task. That's why we offer straightforward, honest and friendly advice, backed up with quality workmanship. Based out of Northampton, we are centrally located so no distance is too far to travel.

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For extra peace of mind we are proud members of the Federation of Master Builders where all members are carefully vetted before they are allowed to join and are required to adhere to a strict code of practice. For more information see the Federation of Master Builders website


New builds & Extensions


If you're looking for a new build house or an extension, ATJ Builders of Northampton can cater for all your needs. All building works are undertaken, from complete new builds and alterations to impact damage. We have extensive experience in making major alterations including supporting entire buildings and installing structural steels to demolishing supporting walls.

A recent example of this was at Front Street, Arnold, Nottingham. This complex expansion project involved turning two retail units into one. This required the upper floors to be supported whilst installing nine pairs of spliced beam anchors to the walls under a central row of spliced beams. The supporting wall was then demolished to create the larger retail unit.

Free Consultation Visit

Occasionally our clients have not yet obtained planning permission before they come to us, which is why we offer a free consultation visit. This allows us to listen to your ideas and discuss the most suitable and cost effective extension for you and your property. Following this initial meeting we will then provide you with an estimated project cost based on your requirements.


If you decide to proceed with ATJ Building & Groundworks we will provide you with a free Design & Planning Service. We can also apply to the local authority for planning permission approval and building regulations on your behalf if you can appoint an architect.

In some instances planning permission isn't always required and work can begin in as quickly as 2-3 weeks.

Once drawings have been finalized and planning process underway we will provide you with a full specification and fixed quotation which is valid for 90 days.


Whatever the size or scope of work required you can be assured that you will have a full-time project manager or supervisor on-site at all times.  All of our tradesmen and appointed contractors are fully qualified or NICEIC, Gas Safe approved and work will be undertaken by a highly skilled and experienced workforce.

ATJ Building & Groundworks offer New Builds and Extensions in Northampton and the surrounding area.





Much of our alteration work involves supporting upper floors and often, entire buildings.

This is an area we excel in due to our extensive experience and one project to note is the Latimer and Crick building in Northampton. This project involved supporting a 3-storey building whilst installing steels to allow the ground floor walls to be taken out for underground parking.

Other alteration work includes:

  • New Openings
  • Steel installations
  • Chimney breast removal




Underpinning is required when a building is subsiding or suffering from ground heave. Underpinning can also be used to enable basement construction by adding depth to the building’s original footings.

The success of any underpinning project is determined by the contractors carrying out the work. In most cases, once the work is completed it is back-filled again within a few days, so it is imperative the work is undertaken by a competent, trustworthy contractor.

ATJ Building and Groundworks ensure all work is undertaken by highly trained and experienced staff who are fully supervised to guarantee our high level of workmanship is maintained.

We mostly undertake traditionally excavated underpinning but can work to any engineer's drawings.


Loft Conversion


Loft conversions are becoming more and more popular and are often a more cost effective option when looking to extend your property.

A loft conversion can create that much needed extra bedroom, study or playroom and with the wide variety of options available we can guarantee the perfect solution to suit your needs. 

Different types of loft conversions include:


The Dormer is suitable for when the existing loft space is of insufficient size for the proposed conversion. It creates additional headroom for the staircase and space required and is particularly useful if looking to create an additional bathroom as it will increase the height above fittings.


This option is often recommended for those contemplating the smaller loft conversion, perhaps for a single bedroom or study. As the necessary height is already available within the existing loft space, roof lights can be installed with minimum disruption.

Hipp to gable

In this type of conversion the hip roof is replaced with gable ends which greatly increases the usable floor space and height around the sides of the property where the hips once were.

Free Consultation & Design Visit

We offer all of our clients a free consultation visit where we will determine the feasibility of a loft conversion and the potential floor space. 

There needs to be a minimum of 2.4m floor to ceil measurement to meet current building regulations, which can be created by lowering ceils on the floor below.

Once we have confirmed these requirements we will then take your ideas and work with you to put them into the design and floor plan.


On your approval of the design we will apply to the local authority for planning permission (if needed) and building regulations. Depending on the type of consent required, work could then begin in as little as 2-3 weeks from the submission of drawings.


Depending on the extent of work to be carried out, loft conversions usually take around 8 weeks to complete and we will aim to ensure minimal disturbance to you and the existing property throughout this time.

With ATJ Building & Groundworks you can be assured that all work is undertaken by a qualified and highly skilled workforce and our tradesmen are qualified or NICEIC, Gas Safe approved.