Knauf Insulation has successfully completed a low energy whole house refurbishment to a mid Victorian terrace in Doncaster, which included the use of their innovative and easy to install Knauf InsulationInternal Wall Insulation (IWI) System. The system has helped deliver a reduction of 52 per cent in CO2 emissions, energy savings of approximately £400 per year, as well as increased thermal comfort for the homeowner.
The aim of the low energy upgrade was to develop a system that could be easily installed by a competent builder, to achieve a ‘whole house – low energy’ refurbishment at a reasonable cost over a normal refurbishment.
Knauf Insulation’s IWI System provided the ideal solution, as it is a highly cost effective method for achieving increased energy efficiency for any type of dwelling, with no specialist skills or equipment required to install the system and it is simple to maintain. The system can upgrade a property to current Building Regulation thermal standards and beyond, consisting of composite thermally engineered studs (EcoStuds) and insulation slabs (Earthwool® EcoBatt), which can be combined to provide greater thicknesses of thermal insulation than achievable by using a single thickness. What’s more, by internally insulating a wall, the heating time for rooms is significantly reduced allowing comfort levels to be quickly reached.
The added challenge was to install a system in a mid terrace house, where the attractive brick frontage proved unsuitable for external wall insulation (EWI). Darren Wedlock, the landlord of the property said he specified Knauf Insulation’s IWI System, as it simplified the process of upgrading solid masonry walls internally, so there was no scaffolding required and the external appearance of the building was maintained.
Along with the IWI System, suspended wooden floor and loft insulation were installed as well as incandescent lighting replaced with low energy bulbs throughout the property. In total Paul Dent, project builder, installed 73m2 of IWI to the property to deliver exceptional energy performance results of SAP 82B with a CO2 emission rate of 1.80 tonnes per annum, compared with SAP 63D with a CO2 emission rate of 3.80 tonnes per annum prior to the low energy refurbishment.
The IWI System comprises EcoStuds – extruded polystyrene laminated to Oriented Strand Board (OSB), which are mechanically fixed to the internal wall. The system uses 75mm thick Earthwool EcoBatt, water repellent, high performance, glass mineral wool slabs friction fitted between the EcoStuds and faced with a vapour check plasterboard sheet. Earthwool EcoBatts fully fill the insulation zone and are in intimate contact with the EcoStuds and plasterboard, thereby preventing any air or draught movement through the system.
Cold bridging and surface condensation is then minimised by fitting 27mm of Polyfoam Linerboard, a laminate of 17.5mm extruded polystyrene and 9.5mm plasterboard around all window and door reveals. Polyfoam Linerboard (27mm) is also installed at all party wall junctions to a minimum width of 400mm and the full height of the rooms, in order to prevent heat loss and the potential for condensation and mould growth in internal corners.
“The Knauf Insulation IWI system provided the most effective solution to this ‘whole house – low energy’ refurbishment,” comments Darren Wedlock. “The whole project has delivered exceptional energy performance and thermal comfort through a very simple and easy to use installation. We have also agreed to allow Knauf Insulation and University College London to install monitoring equipment to enable the measuring of the conditions at the junction of the insulation and the internal face of the solid wall. After five months of monitoring the relative humidity we are pleased to be informed that the results are as predicted in the Knauf Insulation calculation analysis.”
For more information on Knauf Insulation’s Internal Wall Insulation System please visit http://www.knaufinsulation.co.uk/