15th November

The external wall insulation installation is now well under way. Brick slips will be applied once the mesh has been applied and the surface prepared.

Eaves

With the loft insulation and external wall insulation almost in place, attention has again focussed on eliminating thermal bridges and maintaining continuity of insulation.

Eaves details were discussed between Baily Garner, Jenners and CEN. The issue was how to insulate this area in a way that was practical for installation, allowed ventilation of the loft to continue and minimised heat losses. The conclusion was that using phenolic board in the void would be so difficult to install, it ran the risk of leaving gaps for heat losses. Instead, plywood boarding was applied to the rafters to prevent the mineral wool being applied to the void from blocking ventilation to the loft space.

5th November

The wood stove is now in use and has been making a significant contribution to the overall space heating of the dwelling, particularly as the old gas boiler has now been removed. In the interim between this and the new combi-boiler being installed, a temporary cylinder has been installed in the loft which runs on electric immersion. This has allowed continuous provision of domestic hot water to the occupants, crucial at this time of year for a young family.

In-use between the 4th and 11th of November, the electricity consumption graph clearly shows the impact of this system on overall electricity consumption, with a significant spike in consumption over this period. Over the past year of monitoring, daily electricity consumption has

not be higher than during this period. This acts as a reminder of the high fuel bills that would be encountered if electric immersions were relied on as the primary source of hot water.

In the meantime, Heatweb have installed the 500l DPS heat bank in the second bedroom. What looks like highly complex plant work is re-assuredly simple to the end user, designed to make maximum use of the three key heat sources in the dwelling in order of priority (solar thermal, wood stove and gas combi boiler). The Heating Save control system will also ensure that these heat sources are used in the most efficient way possible, learning heating and hot water consumption patterns in order to prevent any wasted heat.

From a management perspective, the user controls will be located separately to the heat bank to prevent confusion and unnecessary interference with settings that should remain constant.

22nd October

The scaffolding is now up, allowing external works to begin in earnest. Before the external wall insulation is fitted, several jobs must be done, including checking the flue will extend far enough through the insulation and brick slips, and extending fixings.

Work has also commenced on the solid floor insulation, using innovative Spacetherm 'aerogel' insulation under chipboard to prevent heat losses through the kitchen floor. This solution is now being considered for the bathroom floor as well.

Is it getting warmer?

After the installation of ground floor insulation and high performance triple glazing with an average U-value of 0.8W/m2K at the beginning of October, all people on site have reported the house feeling far warmer. However, the dataloggers show only a marginal and temporary increase in the internal ambient air temperatures after the fabric improvements, suggesting that the improvements in thermal comfort may be due to other factors such as increased radiant warmth (i.e. the surface of the floor and windows is no longer as cool), and a gradual drop in external temperatures.