The Build Phases

Phase 1 - Site Protection & Preparation

On day one we will protect any vulnerable rooms with appropriate materials and all of the tools and the materials for the initial phases will be delivered. 

To ensure that the site is safe we will secure the existing internal kitchen door, and, if required, install a cat flap.

We ask that you ensure that the areas we will need to work in are as clear as possible.

Also we will probably use the garden to store tools and materials for the duration of the build, so anything valuable or loved should also be moved.

Temporary Kitchen Also on day one we will set up a temporary kitchen in the rear reception room, or occasionally the back bedroom. The Basic Temporary Kitchen consists of a small portable oven and a double induction hob, your refrigeration and storage items, and a section of your worktop, moved from the existing kitchen. The Upgraded Temporary Kitchen provides running water and drainage thus enabling a dishwasher and/or washing machine (depending on the space). If your pipe work allows, we provide hot and cold water to the sink but this is not always possible and this is something we will only be able to determine once on site.

Neighbours It is rare that neighbours are happy about building works in their vicinity so we knock on, and pop a postcard through, the doors of the immediate neighbours so that they can come directly to us with problems or concerns as we are on site and can deal with any issues immediately.

Skips Before we start we arrange for the first skip to be delivered. If you do not have a drive we will need a permit.  and as the skip will be stored outside your house, before it is delivered we may need to block a couple of parking spaces with some bins. Please note that we operate a Rolling Skip Policy, this is outlined here

Phase 2 - Excavation & Clearing

We will remove the existing kitchen, retaining, protecting and storing anything you would like to keep, probably in one of the reception rooms.

We will reroute all heating, hot and cold water pipes to ensure that the rest of the house can function independently while the works are being carried out. If ythe boiler needs to be relocated we will try and work out the least disruptive time to do this. 

We will now be in a position to start excavation and digging footings for the new walls; this process occurs outside the property and, if you have a side return, it will not be necessary to transfer the earth through the house.

As part of the Building Control process any documented Thames Water drainage issues are investigated and highlighted before we start work, however once we start to excavate we occasionally discover undocumented drainage pipes. If this occurs then the District Surveyor will ask that provide details of our subterranean structural solution to Thames Water. This incurs an additional fee to Thames Water (£343 in 2013) and may incur additional labour and materials costs. This is not included in this estimate as it is possible that it will not be necessary and if it is, until we know the size of the problem, we are not able to determine the cost of the solution. It is our expectation that this is the only unavoidable unknown cost in the process.


If there is excavation and underpinning on this project and all of this will be carried out in this phase.

Once any drainage issues have been dealt with, Southwark Building Inspectors will inspect the trenches before they are filled.

Phase 3- Construction

Once all of these issues have been ironed out and the footings have set, we will then be in a position to start to build the new walls.

The new party wall will be cavity walls built with thermo-lite blocks and rendered with a white painted finish. The back elevation will match the existing house and will be either the same as the party wall, or in London Yellow stock bricks. These bricks will not be reclaimed bricks as they are expensive and poor quality, but will be reproduction.

The internal columns that support the steel work will have to be constructed out of engineering bricks to ensure that they are of sufficient strength to pass building control standard.

Using acro props, we will support the upper rear floors. Once this is done we remove the walls that will no longer be needed. Then we will be in a position to install the support steels. The brick work will be cut and pad stones will be placed within the supporting walls. The steels will be installed on top of those and packed with slate. Southwark Building Control will then be invited to inspect our work.

Phase 4 – Roofing, Internal Walls & Sub Floor

When the external walls have been constructed it would be the time to get the door suppliers in to measure up the opening and order the doors and windows.

Usually the roof of the extension is pitched and contains 3 or 4 skylights. The skylights included in the estimate are manual operational Velux with a white finish. The roof will be constructed out of 9” beams and the skylights will be supported by trebling and doubling the beams as pre the structural engineers’ calculations. 

The rain water goods will be redirected.

The sub-floor of the kitchen extension will consist of a Damp Protection Membrane will be a solid concrete floor with sub floor ventilation to prevent condensation and damp.

Any internal walls will be created as per the agreed designs.

Phase 5 – First Fix, Plastering, Ground Works & Additional Works

By this stage, the kitchen design will have been finalised and both the kitchen units and flooring will have been ordered. 

Using the kitchen design, the waste pipes and hot and cold feeds will be run. In addition, the electrician will run the cables into position for the lights and sockets. He will install, and label, isolator switches or sockets for each appliance. These will be positioned behind adjacent accessible units to ensure that any appliance can be turned off without having to remove it first.

If you choose to have under floor heating then this will be installed in this phase, we will lay the pipes and cover then with screed reinforced with steel mesh . This minimises movement in the subfloor, thus protecting the final floor covering but also help conduct the heat. We will pressure test the UFH and all other pipework once it has been completed. 

The boiler engineer will connect up to the boiler, zone valves and pump and we will install isolator valves on the incoming hot and cold feeds so that the water supply can easily be switched off should any tap or appliance require servicing. Any other components that may break down will have inspection, or access, hatches installed where possible, so that maintaining the kitchen in the future will be straightforward.

Any external groundwork that need to be reinstated have not been include in this cost. These should be discussed it this point so that this work can be carried out while we compete the internal works.

Phase 6 – Flooring & Fitting

In this phase the flooring will be laid and the kitchen will start to feel less like a building site. The doors will be fitted and the initial decoration will be carried out, however a final coat of paint will be required once all of the work has finished.

The kitchen units will be fitted to the walls and adjusted to ensure that they are secure, true and level. The sink and hob will have to be on site by now as they will be required by the worktop company to template.

At this point the worktop should be ordered, as it will be necessary for a template to be created. It would also be a good time to order the rest of the appliances to ensure that they are available for the second fix.

The secondary rooms such as the utility room, pantries and WC’s are included in this stage.

Phase 7 – Second Fix & Finishing

This phase always take a long time as it is important that the finishing details are perfect.

The sink & tap will be fitted; the plinth and end panels installed and skirting boards will be fixed.

The worktop will be installed by the suppliers.

The lights and sockets will be fitted by the electrician and the compliance certificate issued. 102Interiors will ensure that a copy of the certificate is sent to Southwark Building Control and, you get the original, and we will keep a copy on file for our records.

Any gas appliances will be fitted by the gas safe contractor and their work registered directly with Gas Safe who will contact the council to inform them that this work has been carried out to the correct standard.

Southwark Building Control will be invited to inspect the finished kitchen and utility room and sign off the work. Once this has been done then they will send you a Completion Certificate.