Double-glazing film - any use?

In our previous house we fitted Perspex sheets on magnetic strips over single-glazed windows that we then removed and set aside so we could open the windows in the summer. Thought I would try the same thing on one window that we never open in an unheated small room using Stormguard ‘Double Glazing Film’ (purchased from Homebase). Easy to fit and the room feels warmer but sadly my MIN MAX thermometer does not record any significant increase in the room’s temperature. Fitted some of the film also on the single-glazed panel above the inner front door, and over the back door. Cost – about £10.

The loft is finished

Finally finished the insulation in the loft, having removed as much of the flooring as I could to roll additional insulation under that, and in some cases building a new floor on 50mm battens above the existing joists so that I could fit a proper depth of insulation under it. Also had to get as much insulation and draught-proofing as I could on the hatch into the loft.

Cold air comes down chimneys

We have an open fire in the sitting room and dining room on the ground floor. Of course the cold air comes down both of these when they are not in use which of course is most of the time. Made a timber cover for the sitting-room one – not a perfect seal but cuts out much of the draft and, painted black, is hardly noticed.

What is the temperature in here?

Bought an additional MIN MAX thermometer to keep inside the house to measure the temperature in different parts of the house, see what effect different boiler settings might have at different times of day in different parts of the house, and see if I could measure any good effects of all this work. Began a daily log of outside MIN MAX and inside MIN MAX, moving the inside one around to different parts of the house.

Insulating the loft - part two

Due to the existence of the cupolas and the already floored areas, let alone the cold water tanks and the hard to reach eaves, there did not seem to be much point in building a layer deeper than 270mm. Who knows whether, given this situation, it was worth even doing what I did, but Homebase were selling SPACE insulation Blanket and Loft Roll at 2 for 1, so the total bill for the insulation only came to £49.33: although it took a fair few days to complete.

Time to tackle the loft

When we bought the house the loft had fibreglass blanket laid between the joists to an average depth of 170mm. Newspapers stuffed into odd corners appear to date this deed to the late 1970’s. When we came we floored about a third of the loft so we could use it for storage. This of course is now covered in a ton of stuff not easily moved. I reckoned that there were about 32 square metres which I could cover with either 100 or 150mm wide insulation, laid over or between the joists, to achieve a minimum of 270mm overall.

Can I generate my own power - or heat?

Rang the Energy Saving Advice Centre in Edinburgh to register my interest in installing Solar Water-Heating Panels on my roof and ask for someone to come and tell me if it was feasible and worthwhile.

The newly insulated cupola

Here is the cupola from above.

Time to tackle the cupola

It’s lovely to have the light coming down the centre of the house but the cold draught that comes with it can almost slice your neck off. It measures 1.7m by 1.9m and would take a scaffold to reach it so fitting a Perspex sheet over it from beneath (as done to the one in the bathroom) was out of the question. I suppose getting new double-glazing units for each of the eight triangular panes might be the ideal solution but you can get around it in the loft space and covering it from above with plastic seemed worth trying initially. After testing samples of bubble wrap and sheet plastic I concluded that light grade small (4.2mm) bubble wrap was least intrusive, excluded least light, and should surely offer good insulating properties. Macfarlane Packaging offered the best prices on rolls of the right spec of the right width (1200 mm), even though it meant buying 100m in length (£43.68 including delivery). After a couple of shots at cutting and joining for the triangular sections the cupola now has a tailored ‘hat’, clipped to the edge of the glass panes, with the separate vent at the top of the cupola also insulated with two bubble-wrap covers. All covers easily removable if required, for instance for ventilation in summer.

Energy Monitor Trial

Borrowed one of the 12 ENVI Real Time Energy Monitors (www.currentcost.com) from Edinburgh City Libraries. To find their stock of monitors on the online catalogue put 'Energy Monitor' into the Keyword field on the search page. Fascinated to see my electricity use spelt out on a screen in front of me. I duly logged for a week (maximum loan period) the major ups and downs. Most of us probably know that kettles and irons and tumble driers consume humungous amounts of electricity, but I didn’t find it made much difference knowing what this was costing me in pounds per day as few people run a kettle or a kettle or an iron for this long. So it was the daily totals that were of most interest and particularly the point when you think nothing is on in the house but the screen still says you are using 245W. I was alone in the house that week and my average per day was 11.5 kWh. I handed the ENVI back in to the Library a little reluctantly but not bursting to have my own.

My home energy report comes back

Received my ‘free home energy report’ from the Energy Saving Advice Centre. A pretty crude analysis saying I could improve my rating from an E to a D and save £479 per year if I fitted more loft insulation, more controls to my heating system, (although I had most of these already) solid wall insulation (extremely difficult in a property like this) and double glazing (ditto).

Home Energy Check - advice from others

Sent in my home energy check questionnaire to the Energy Saving Trust’s Energy Saving Scotland advice centre in Edinburgh.

Light bulbs - the halogen problem

I’m stuck on the following – the halogen tracks I have in the kitchen (150W) and a study (100W), - these lights are on a lot but I know I cannot replace with LED’s without replacing the whole track and transformer. This will have to wait. We have a dimmable uplighter with a 200W halogen bulb in our living room that is used a lot which we repaired recently – I should cost replacing this with an LED uplighter. There are also two cupboard lights that use little 60W tungsten strips, but as these are only on for a minute or two every day I am not going to worry too much about them. Other than that there are a couple of desk lamps that have tiny halogen or tungsten fittings that are not used a lot which I will phase out in time.

Light bulbs

Carried out a light-bulb audit. This revealed that I had low energy bulbs fitted in only 7 ceiling pendant lights, leaving a total of 33 light-fittings with tungsten or halogen lamps that in theory ought to be replaced. The only other lights I could leave unchanged were the two worktop fluorescent strips in the kitchen (although each uses 75W), and one in an understairs cupboard. Not that easy to find SES fittings giving the right brightness for reading, or fittings for spots of ceiling downlighters that did not take 20 minutes to warm up, or fittings for dimmable lamps, but Asda and Homebase were selling the standard Philips Genie sticks and GE Spots for a good price and I sourced the more difficult ones on the web from Eco-Friendly Lightbulbs and Efficient Light, both of whom were good enough to take back lamps that did not perform as intended (usually related to taking too long to warm up, or not being compatible with dimmers). To date I have replaced 22 bulbs, at a total cost of £59.73, achieving a reduction in power usage from 1300W to 294W.

A plan of action

So with a bit of reading under my belt (which also included a PRISM book on Home Insulation - see image left - I found on my own shelves that I bought in 1981 when we moved into our previous house) I drew up a list of what I could tackle in my own home.

1 Attack draughts – from windows, doors, chimneys, cupolas
2 Re-consider the whole area of double or secondary glazing on those windows (we’d actually started on this a while ago – see below)
3 Increase the depth of insulation in the loft – and deal with the cupolas
4 Change as many light-bulbs as I could to low-energy bulbs
5 Monitor our energy use more closely and use this to reduce our daily energy usage
6 Look at whether we could generate any of our own energy or at least get the sun to produce hot water for us

Getting started – some reading and inspiration

In November last year I went to a conference put on by Changeworks and Edinburgh World Heritage on how old buildings could be adapted to use less energy. Howard Liddell of Gaia Architects gave a searing talk and promoted his book ‘Eco-minimalism’ as well as David MacKay’s book ‘Sustainable Energy, without the hot air’ (available free at his site). They are both good reading – David’s being exhaustive and authoritative but, as the title implies, straight talking also. Both Howard and David (who recounts some of his own experience with his own house in Oxfordshire) push three messages very hard – one, that there is quite a lot we can do as individuals to consume less, two that our own houses do matter, as housing produces a large proportion of carbon emissions and three that it is the simple things like stopping draughts and heat-loss, rather than the expensive gadgets that Howard calls eco-bling that can make the most difference.

What we had already done in the house

Since buying the house in 1998 we hadn’t been completely inactive.

The windows – secondary glazing and draught-proofing. When we bought the house 10 of the windows already had secondary glazing fitted (Everest, aluminium sliding in brush-fitted track, no date). Finding much of this clunky, ill-fitting and difficult to clean in 2005 we removed this from 4 of these windows, and had these fitted with ‘Sealglide’ brush draught-proofing, serviced, and put back. We were pretty pleased with this work – the windows looked better, let in less draughts, also less noise, and the removal of the secondary glazing caused no appreciable loss of heat. Other windows received moderate ‘servicing’ to fit more tightly when closed but we could not afford to give them all the full draught-proofing treatment. Some of the windows (in many cases the upper window of the sliding sash) had no provision for opening at all and we firmly sealed them to again minimise draughts.

The windows – curtains, blinds and shutters. In the living room we are lucky enough to have the original wooden shutters over both windows – they are not the tightest fit but mean we don’t have to have curtains hanging over the radiators that are under these windows. Two downstairs rooms also have shutters and all other windows have curtains and/or fabric blinds on them, in some cases both.

The boiler. In January 2009 a major part failed in the gas boiler that we inherited with the house (precise age not known): this heats our water and provides central heating to radiators in 12 rooms, (in summer we turn off the boiler and use an immersion to heat the water). We made a snap decision to replace it with a new condenser boiler (Greenstar 30 CDi Conventional). It is a SEDBUK A-rated appliance, and although in retrospect it might have been nice to have had the time to lok into a fuller range of options including air-source heat pumps, (a) I didn’t know about these then and (b) it was damn cold at the time.

The house

It’s a good stone-built Edinburgh house, at the western end of a terrace of four built around 1880. Being end of terrace (the story goes that the architect who built the terrace kept this one for himself) we have windows at front (NW), side (SW) and back (SE) - great for gaining light, but great also for losing heat. Two cupolas also bring light and let out heat through the top of the house. One lights the stairs that lead from ground to first floors; the other brings light into the bathroom on the first floor. Both in fact ‘borrow’ light from the roof space above the first floor, to where it is fed through two sloping glass skylights in the flat roof above. We’ll talk about the roof space later.

The Windows
There are fourteen of these, and the inner front door is also mostly glass (there’s a timber outer ‘storm door’ as well). Two of the windows are bay windows each with three separate sash windows, and three are double sashes also divided by stone mullions, so in terms of sash windows we have a total of 21 of these. And they are not small – on the ground floor each bay window has a total glass area of over 4 square meters, and each individual sash window on the first floor has a glass area of nearly 1.6 metres.

These 21 windows light a total of 12 rooms, the five on the first floor being bedrooms plus one study (plus the bathroom), the four on the ground floor living rooms, plus another study, and the rooms in the basement a further bedroom and bathroom plus a workroom and utility cupboard.