Frequently Asked Question
How do I know the walls are full?
Each system has a defined pattern of holes, which has been tested to verify that it results in a complete fill. Most systems have an automatic cut out, which actuates when the adjacent wall area is full. There is tolerance in the injection pattern so that the material will flow past the next injection hole.
Is the insulation dense?
No, as the insulation is contained within a masonry wall, it doesn’t need to be ‘dense’. For insulation and other purposes, a light density is better. Before installation, the technician will undertake a quality test to ensure the insulation will go into the wall at the right density. He will also note the amount of material used, to know that sufficient insulation has been installed.
Note: Drilling a hole in the outer wall and testing the cavity fill with a rod or pencil will not provide any meaningful information.
What about the ventilators that are in the external wall?
Ventilators supplying combustion air to fuel burning appliances must be safeguarded. Similarly, ventilators at ground level that ventilate below timber doors must be safeguarded. The technician will investigate them to check they are already sleeved. If they are not, the technician will remove them and seal around them to stop them being blocked by the insulation. Other vents, which may be redundant, such as cavity vents or vents that are used to supply air to open fires in bedrooms may be closed off. The technician should discuss these with you. Redundant airbricks may be filled.
But my house has painted areas?
The technician will fill all the injection holes with mortar to match the existing as closely as possible. He will use a mix that closely matches the existing colour and texture. On pebbledash finishes, he will apply pebbles to the surface to match the existing finish. After weathering, the holes are difficult to see.
Normally, we paint the injection holes. Unfortunately, even if the original paint is used, it may not match due to weathering. So it may be necessary for you to consider painting the area, after the mortar has dried.
You should discuss and agree what will be done with the surveyor.
Click here to continue reading.