Ask an Architect: Can I Make My Home More Ecofriendly?
The idea of giving your home a major green makeover may seem daunting, but an eco retrofit could be easier than you might think
Here are eight ideas to consider to help you make the most of ecological design, technology and building techniques in your home.
While there’s still a high percentage of homeowners who live with single and double glazing, it would be like skipping a step not to talk about triple glazing on the ecological front.
As the name suggests, triple glazing, which features in this eco house near Aberdeen, consists of three layers of glass (with two hermetically sealed, gas-filled spaces in-between) and is the latest in glazing efficiency.
This thicker, heavier glazing is not always possible – for instance, if your building is listed or in a conservation area – but creating a new extension offers the chance to use this ultra-efficient type of glazing.
You may find the costs compared to double glazing are higher. However, if you’re investing in a good amount of thermal insulation in the walls of your new extension, it will be worthwhile doing the same for the glazed areas. You should also find your energy bills are lower, justifying the investment.
If you would like to replace your existing, single-glazed windows, speak to your architect about the choice of windows available.
An efficient system to heat your water and radiators is very important. Underfloor heating tends to be very effective, as it heats up a room thoroughly (hot air rises) and uses relatively little energy compared to radiators. Water-based underfloor heating is most efficient in this case.
It’s easy to forget about heat loss through ventilation – air bricks and trickle vents are effectively crude holes in your outside walls. Your stale air is removed, but you also lose heat, which you have paid to generate in the first place.
A much more efficient way is to use heat recovery systems, whereby the incoming cold, fresh air is heated by the stale air, so it enters your rooms warmed up. This system only works if you do it for the whole house, so it’s aptly referred to as a whole-house ventilation system (for more on this, see ‘Consider a Passivhaus’, below). You can install it if you have a loft space, as the equipment needed takes up a bit of room.
The extractor fan in this kitchen – housed inside a sustainable Douglas fir box – sucks air upwards and into a heat exchanger above the ceiling, which recycles the warm air and expels the cold.
This ivy-clad outhouse looks beautiful, but it’s also a good way to illustrate the idea behind well-designed insulation, in that there are no gaps through which you would lose heat. (It’s also a lot better looking than a photograph of foam insulation boards…)
Building regulations set out minimum thicknesses for thermal insulation, which your architect can advise you on. If you would like to improve this insulation and lose less heat through the walls, you can always add insulation to the interior side of all external walls. This is either insulated plasterboard or insulation boards with plasterboard on top. Note, though, that this will reduce your internal footprint, so this solution is not for everyone.
You can get very thin sheets or rolls of ultra-dense insulation for particular historic interiors, which are only 1-2cm thick yet still greatly reduce heat loss. The thinner the insulation you add from the inside, the less deep, for example, new window reveals will be – and you won’t lose any historical features.
Lighting is very important and, if in doubt, most homeowners tend to be prudent and plan for more light rather than less. By adding lots of lights, though, it can easily be forgotten how much energy they use.
New LED lights are more expensive than halogen or incandescent bulbs, but they are much more durable. Paying a bit more upfront will give you big cost savings in the future and, since you don’t need to replace LED lights for 10 years or more, there will be less waste, too.
If you plan on replacing your current ceiling lights with LED lights, it’s usually quite easy, as the sizes for spotlights, for example, are mostly similar. However, since LEDs are not strictly speaking bulbs one can replace, they are usually integrally linked with the lamp, so they cannot be separated. If in doubt, speak to your supplier or architect.
Browse a beginner’s guide to LED lighting
If you have a sloping roof on your property, chances are you can fit solar panels to it – the more south-facing the better. On flat roofs, the panels need to be placed on manufacturer-specific stands at an optimum angle and direction.
If you are in a conservation area, there are specially made ‘roof tile solar panels’, which, as the name suggests, resemble more traditional roof tiles.
Discover what more experts have to say about installing solar panels
The new extension to this house fits in well, even though the roof tiles don’t match. Instead, a much more efficient roofing system has been used. Rather than traditional roof tiles, it’s possible to use more airtight roofing insulation, which in turns keeps more heat in. Tiled roofs are ventilated, which removes lots of heat instead of trapping it inside the house.
When it comes to the walls, instead of bricks, use blocks, which have small air bubbles inside for improved insulation. If you can, add the insulation to the outside and add render onto it (although this may not work in conservation areas).
Add lots of insulation, both below the floor and under the roof, to act as a warm coat for your house. If your house is from the 1930s or later, you most likely have external walls with an air-filled cavity (which is still better than no cavity). You can fill this space with insulating foam by injecting into it through regularly spaced holes from the inside or outside. This is typically known as cavity wall insulation.
Why not literally make your house ‘green’? No, not by painting it, but by swapping the standard tiles for a gorgeous green roof. You’ll need to start with a flat or low-slope roof, as the greater the slope, the more complicated the system becomes – so, again, this could be one for a planned kitchen extension, a garden room or even a shed.
You can choose from a very low-maintenance option – sedum – which you inspect twice a year, or a more elaborate version as shown on this Californian cabin, where native shrubs have been planted to create a green mosaic.
A green roof not only gives wildlife a new home, reduces water run-off and improves your amenity space, it will also look beautiful.
Tempted? Read a beginner’s guide to green roofs
Last but definitely not least, is the much talked about Passivhaus, or passive house, standard.
A pure Passivhaus is unlikely to be an option unless you’re building a new home from scratch, but there are plenty of ideas to steal and retrofit. Born in Germany and the Scandinavian countries, the Passivhaus is a contemporary way to build very airtight houses, where all incoming air is warmed up by the stale air before being pushed out. Thermal efficiency exceeds all current building regulation norms.
To adopt the key idea behind this new way of thinking, try to combine thermal insulation and heat recovery (see the points above about heating and insulating), then you will be one big step closer to a true passive house. When you apply these principles to an existing house, you might not get the same results, but it will be a big improvement nonetheless.
A lot of the success of the Passivhaus comes down to the many ingenious details geared towards making the property more airtight and reducing so-called ‘cold-bridging’ – in other words, addressing the heat loss that occurs where different materials meet, a detail that has frequently been overlooked in other types of building.
Do you have plans for green upgrades to your home? Share your thoughts in the Comments below.