Technitherm – Hard To Treat Cavity Wall Insulation Solutions

Hard to Treat Homes / Multi-storey Blocks / Residential / Apartments

policy_17_hard_to_treat_cavity_wall_insulation – download and see if your homes qualifies as hard to treat

Upon first glance, most people may not have thought that a building in a place as warm as Gibraltar would need insulating. Despite the warmer climate, the high temperatures and high humidity still play their part in creating problems of a different nature to that of being cold and damp, as seen in a typical British winter.

We insulate our houses back in the good old UK to keep warmer in the colder months and save money on heating costs, whilst staying cooler in summer, reducing extremities of  temperature and generally feeling more comfortable all year round.

The problem presented to us by the Government of Gibraltar, was that a large chunk of the existing housing stock and high rise apartments were suffering from a build-up of condensation within the wall cavities, caused by the high humidity and the difference in temperature between the inside of the air conditioned rooms and the much warmer air present within the cavity wall construction. The air was not being circulated quickly enough to eliminate the condensation build-up, so another solution was required to prevent this problem getting worse.

This is where the Technitherm foam system comes into the frame, thanks to its closed cell structure and excellent thermal performance (K values as low as 0.25). We are able to install the Technitherm foam system into a cavity wall to provide a complete fill, leaving no air pockets for condensation to form in and track across to the inner leaf.

Technitherm bonds to both the inner and outer leaf, providing an air tight envelope of foam insulation, whilst adding a fair degree of structural stability to the wall construction.

Comparison of Technitherm to other types of insulation

Product K-Value Thickness U-Value Airtight? Cures Condensation?
Fibre 0.040 85mm 0.441 No No
Polybeads 0.038 85mm 0.422 No No
PU Foam 0.025 85mm 0.280 Yes Yes

So how does it work?

Technitherm foam insulation is injected through a pre-determined series of small holes (12mm diameter usually through mortar T-joints). Because the Technitherm system is injected as a liquid, it can spread quickly throughout the cavity and starts to expand and slowly rise, working its way into every nook and cranny to provide a complete (full fill) envelope around the property.

The actual installation process involves checking the property for any incompatibility issues, and working with a high level of attention and care to inject the Technitherm system from bottom to top as required.

Technitherm will still allow the walls to breathe, that is to say the foam will allow water vapour to pass through to the outside world, though thanks to its 90% closed cell structure, water cannot pass through the foam by capillary action from the outer leaf, making it the ideal choice for buildings in high exposure areas, facing the elements. Even wind driven rain will not get to the inner leaf, and the same goes for rising damp.

Can anybody install the Technitherm system?

Only Technitherm trained installers who carry a full BBA license can install the Technitherm foam system, meaning that because of the stringent control and quality assurance measures in place, each installation is carried out in accordance with the Technitherm installation guidelines. The Technitherm system simply is not sold to any installer who hasn’t had the required training and approval, and who also isn’t in possession of a BBA installer number.


Technitherm is manufactured by Isothane Ltd