Cavity Extraction – the Joyner Solution
We extract, we fill or we can EWI
It has been a directive of just about all of us for many years now that to keep a house warm we must insulate it. Well this is true, but you also have to ensure that the type of insulation you use is appropriate for purpose.
It transpires that some homes are not suited to the cavity wall insulation remedy, and this particular solution to heat loss has had side effects.
The manifestation of internal damp being sighted as the most common negative results. We have a solution to the problem, removal of cavity wall insulation!
We have specialist equipment and specially trained individual members of our team to ensure that should you require this service, we can delivery quickly, cleanly and effectively.
The drive to improve U values in cavity wall construction by filling the cavity with loose insulation, has in some instances caused issue that may mitigate the theoretical thermal improvement. As it becomes more evident that this drive should have been tempered with more reflective testing, practical experience and building knowledge with a much greater onus placed on quality assurance, solutions to the problem need to be found.
Initially removal of failed insulation is an imperative. Effectively, once wet from penetrating or rising damp, the insulation put in place to improve U values can cause direct heat transfer out of the property and cold bridging. Previously the removal of loose cavity fill insulation was a laborious and time consuming task, which to complete properly required substantial quantities of the external façade brickwork to be removed and the insulate to be dragged out by hand.
We now offer a more expeditious solution and service to remove any contaminated insulate. By negatively pressurising the cavity, applying a vacuum through removed masonry at low level and then breaking down the insulate with compressed air applied through drill holes across the façade, insulate is removed. To ensure cleanliness of the cavity, bore scope surveys, with real time video footage or still photography, can record the removal of failed insulation and quality assure the cleanliness of the cavity. At the same time, and prior to making good, the cavity is cleaned at low level, to achieve a debris free cavity to a level approximately 1 brick below the external DPC.
Once the contaminated insulation has been removed and the brickwork/masonry replaced, time for the cavity to air dry should be allowed. This normally is in the region of 6-8 weeks. After this time thoughts should turn to attaining appropriate U values and while the removal of failed insulation can only improve the individual property’s current situation, at best it can only return values to the pre-insulation state. Alternative applied energy efficiencies and insulations should be considered including external wall insulation, cavity wall insulation with hydrophobic or moisture resistant materials.