40% House

Martin and Jane Normanton have dramatically improved the insulation and heating system of their solid–wall house over a period of years. Their project shows how very substantial emissions reductions can be achieved on a limit budget by making changes in installments and by using DIY.

About the house


The house was constructed in 1903 in Walsall in the West Midlands. Like nearly all houses built before 1928 it has solid brick walls which have negligible insulation value. It faces roughly South at the rear. Martin and Jane moved in with their two children, then in primary school, in 1983. At that time the house had no insulation and was heated by electric storage heaters.

Why did they want to do it?
Both Martin and Jane have always disliked waste and planet abuse. Martin has a long interest in energy efficiency and as soon as they moved into the housed installed the obvious measures of loft and cylinder insulation and draught proofing. It was a growing concern about climate change that persuaded them to go far further than their original efficiency measures.

About the renovation

Heating
In 1999 Martin replaced the storage heaters with gas central heating powered by a Worcester Bosch Greenstar HE 30 condensing combi boiler. With the help of a trustworthy and willing plumber he installed oversized radiators, a programmable room [house] thermostat, Thermostatic Radiator Valves, and ensured that all pipes running in unheated areas were fully insulated.  If they were doing the work now they say they would upgrade to the HE Plus version of the boiler, which works with an intelligent room thermostat to modulate the boiler down as the desired room temperature is approached.

Insulation
The insulation of the solid walls has been a major project and Martin has achieved it in installments, following priorities and opportunities as they arose. The first stage in 1998 was to internally insulate walls in the bathroom and one bedroom.

In 2002 he insulated the party wall between the garage and the house. Garage wall insulation need be neither weather proof nor professionally finished and so lends itself well to DIY. It also allows insulation to be fitted on the outside of the wall- which is always the best option for minimising cold bridging.

Martin bought 100mm rolls of fiberglass insulation specified for wall as well as loft insulation (presumably a little stronger) from FGF of Birmingham. These are hung from battens at the top of the wall inside the garage in two staggered layers to give 200mm of insulation, and then covered and very slightly compressed by paneling made of old 1960s hardboard doors set sideways on timber studs.

In 2003 he bit the bullet and installed internal wall insulation in the front of the dining room. The project included installing a very large low-e double glazing sealed unit inside the original window, thus preserving the appearance of the house. A separate ventilation aperture is provided three feet to one side of the window. The work was mostly done by a neighbour’s son chosen for availability, easygoing nature and lack of preconceived notions about normal building techniques! Half the cost was in having an expert replace the period coving for £600.

Pictured: The low e-double glazing window

In 2005 Jane wanted a new kitchen, so Martin took the opportunity to install internal wall insulation on the rear wall of the kitchen. He used 100mm polyurethane insulation sheets held in place with battens and very long fastenings. The space between the battens was filled by 25mm insulating quilt (sold as sound insulation), and finished with plasterboard.

The sheets provided an effective vapour barrier and all gaps were carefully filled with expanding foam. This room has a solid floor, so the polyurethane insulation was carried down into a 600mm trench dug along the inside of the wall, and held in position by backfilling with a weak dry-mix mortar.

This still leaves two uninsulated downstairs walls; they have been left until last as they have bay windows.

Hot water
Hot water for the shower and bath are provided by the combi boiler. Hot water for the kitchen and bathroom sinks is provided by individual electric water heaters with 10 litre storage tanks. Martin says that the small quantities of water used in the sinks are not an efficient use of the boiler and that much of the heat is lost in the pipe run- not to mention the time wasted waiting for it to arrive. Although they are not as well insulated as Martin would like, the tanks are only set to hand hot and so heat losses are low.

Appliances and lighting
About 2002 Martin acquired a plug-in electricity meter to monitor the use of individual appliances.  This revealed various horrors, and was promptly named “The Judge”

The Judge found that Jane’s halogen desk lamp used 4 watts when “off” – it is now awaiting recycling. The 22 year old fridge-freezer was also quickly condemned, but won a reprieve as they could not find a modern replacement with a big enough freezer. After external insulation with 60mm of polyurethane it is now about a ‘C’ rating.

The dishwasher was found to use 1.5KWh per wash, and has been largely replaced by Martin hand washing using about 0.3KWh for HW. The washing machine is an ‘A’ rated Bosch. The tumble drier was last used in 2004 and sparrows now nest in its vent.

Most lighting is by low energy bulbs (some as low as 5W) in either uplighter shades or paper globe shades. Bathroom and bedroom lights which are rarely on for any length of time use 40 watt bulbs; they last bought a 100 watt bulb in 1987.

Water
They have a Swedish Ifö Cera toilet, which uses only 2.5 to 4.5 litres of water per flush (the most used smaller flush is 60% less than conventional British models). What were the main obstacles they encountered?
Martin and Jane’s complex wall insulation involved greater hassle and time than the conventional solution of off the shelf insulated plasterboard, which offers relatively low insulation levels. As Martin says, this is only possible if you have the time and knowledge to get deeply involved. They have avoided problems with builders by doing much of the work themselves and employing friends and neighbours.