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Stage 2

External wall insulation, what and how we do it.

So you have chosen Warm Walls Insulation Ltd to transform the exterior look of your home while applying External wall insulation to upgrade the energy efficiency of the existing external walls and conserve energy. 

Before we can begin we need to do an on-site survey, this is usually done during our first visit with you where we give you an itemised quote.

On Some houses we have to deal with on-site services these are usually an existing Gas meter mounted on a wall we intend to insulate or electricity supply cable over head that is surface mounted to the walls. (houses with external meter boxes normally have underground cables). if either of these services exist an application to have them moved with have to be done in advance of starting on site. If an application to have services moved is required Warm walls Insulation Ltd will help you make the application. 

The Charge is normally in the region of the following:

ESB surface mounted cables: €400.

Gas Bord €480.

First day set up: On the first day we place plastic sheeting down (Pic 1) and then install the scaffolding (Pic 2). The scaffolding is erected by a specialist scaffolding company who holds all the relevant Health & safety training & insurances.

When the scaffold is erected our team start preparing your home for the installation of external wall insulation. 

Step 1, Remove reveals: All existing reveals are removed around window and doors (Pic 3). This allows for the installation of 20-25mm of insulation to be fitted to reveals (Pic 4) and eliminate cold bridging at these junctions. 

Step 2, Adjust services: Services such as the soil waste pipe from the bathroom and other drainage services around the house have to be temporarily adjusted, this normally renders your services suspended for about an hour.(Pic 5)

Step 3, Removal of external lights, brackets, side gates etc.

Step 4, Installation of Base track/Starter track: the base track is placed at Damp proof course (DPC) level this normally occurs at the plinth. The base rail is an aluminium track mechanically fixed to the wall, this is set up using a level and allows for the installation of our insulation boards to remain level throughout the boarding process.

Before installing External Wall Insulation

Pic 1

Pic 4

Before applying External Wall Insulation

Pic 2

Pic 5

Starter tract for external wall insulation

Pic 3

Pic 6

Stage 3


Step 5, Once the base track is in place and all services adjusted we start the boarding process. This involves fixing the ESP insulation boards to the walls, starting with the first row being placed on the starter track already installed. The insulation boards are stuck in place by applying a special adhesive to the back of the board, this adhesive is also used to position the boards plumb and square. After the first row is installed the second row is installed in a staggered pattern similar to that of a brick wall, known as a stretcher course.

Step 6, Once all the boards are in place and the adhesive has cured, mechanical fixings are installed  in each board to a specified pattern and quantity, usually 5 fixing per 120cm x 60cm board or 7 fixing per m2. The fixings are installed by first drilling through the board and into the original wall. A fixing which comprises of 2 parts is inserted then hammered home, which causes the inner pin to expand, thus holding the fixing and board in place. Before moving onto the First base coat stage each indentation around the fixing is filled with a mix of base coat.

Note: It is very important that the boards and mechanical fixings are installed correctly to avoid any possible cracks or failure of the system in the future, each stage of the process is as important as the next as well as identifying problem areas before commencement on site. 

Step 7, Once the boards and mechanical fixing are installed, we begin the base coat stage. A thin layer of base coat is applied using traditional plastering techniques, and while in it's wet form we apply a reinforcing mesh to the base coat and trowel it in. A double layer of mesh and base coat is applied 2 meters above ground level around the entire house as added protection against day to day traffic. Also at this stage reinforcing mesh and base coat is applied to all important junctions such as, at the corners of doors & window openings. Additional corner meshes, window seal beads etc. are added at this stage.

Step 8, Below Plinth level: A different type of insulation known as XPS insulation is installed below the starter track. This is normally recessed about 20mm, similar to traditional plaster detailing at this junction and is finished in accordance with the manufacturers instructions.

Step 9, At this stage we apply our second base coat over the first to give added strength and to allow us to smooth of the base coat in preparation for the final Acrylic finish 

Stage 4


Step 10, When the Base coat has dried out a primer coat is applied by painting it onto the entire surface of the building. The base coat normally comes in the same colour as the chosen final colour to be applied next.

Step 11 Once the primer coat has dried, we now begin our final layer of acrylic render. this layer is applied by towelling the acrylic over the all areas insulated. This part of the process has to be timed properly and the flow of work planned ahead in order to achieve a continuous render without any lines showing as the acrylic finish has a minimum set time. For example, when rendering a large wall the entire area must be completed in a phased manner to avoid any start/stop junctions showing in the final render. This usually happens when inexperienced installers stop for periods longer than the set time. The Acrylic render comes in a large choice of colours leaving your home with a finished look and low maintenance. Normally the finish just need to be cleaned and can go un-painted for 10 - 15 years minimum. 

Step 12, Once all rendering work is complete we reinstall all fixtures and fittings, tidy up and remove scaffold leaving your home with well insulated walls and entirely decorated on the outside. All you have to do is sit back and enjoy your reduced energy bills and the comfort and warmth of your new insulated home.

This explaination is a general one that only deals with external wall insulation finished with an acrylic render.

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