Think about how an Energy Efficient Home Design will improve your tenant’s lives
When it comes to energy efficient homes, we all want the same things: a home that uses as little energy as possible while retaining as much heat as possible to make life more comfortable for the occupants.
That’s a given, and it doesn't sound all that difficult or expensive to achieve! In theory it’s quite straight forward, but we all know that when letting property, theory and practice, in the real world it can be quite different.
The number of people involved in the construction or refurbishment of a rental home is immense and with each person comes the risk that your goal will get diluted.
So, by the time your property is built or renovated, and there have been dozens of different people involved (each with their own take on how it should be done), it’s really easy to end up quite far away from your original goal of achieving the greatest energy efficiency that’s possible.
Planning comes first
There are a few things you’ll need to think about if you want to get it right and reduce the chances of issues cropping up during the project.
According to energy efficiency expert jeremy@eco-home-essentials.co.uk in his opinion there are two main aspects that are crucial to achieving an energy efficient home (and they apply equally to new build and retrofit): Insulation and Ventilation.
There are other issues to look at if you want to keep going, such as the heating system, but here we look at these two, and Jeremy outlines these in his free guide: "Simple Energy Reduction Tips" e-book
As you consider each of these issues, you’ll discover how they have a knock-on impact on other aspects of a build or refurbishment. This is why it's so important to cover everything at the design stage, before you start work. For example, your insulation will have an effect on virtually everything in your home, from the air quality, size of your boiler, cooling issues, ventilation, window choice etc.
If you want your property to retain as much heat as possible it stands to reason that you’ll want to choose the right insulation and have it fitted correctly. But choosing the right insulation isn’t just a matter of picking one and going for it.
If you’re using a light weight construction method such and structural insulated panels (SIPs) or timber frame etc you’ll likely choose a different type of insulation to someone who has an existing property that you are renovating, and want to add insulation to the cavities or insulate an old solid wall, either internally or externally.
Plus, no matter what type of construction method you choose there’s no one right insulation material. You’ll face a choice of at least several types and it will be up to you and your architect or builder to pick the best one for your project.
While you may get away with a rigid insulation board on a new build or extension, you'll want to go with a natural breathable insulation for an older home. But insulation on its own is not the right answer either, as you should be adding breather layers and vapour control layers as well. These reduce the amount of water vapour that can get into the insulation layer.
Many rentals are older properties, so it’s essential that with an older property you maintain breathability in order to reduce the risks of damp and interstitial condensation. To do this, you must choose the correct installation materials so that your insulation can absorb and release water vapour, depending on the atmospheric conditions. It should also be dense enough to prevent the property getting over hot in summer.
One of the insulation materials Jeremy recommends is wood fibre. It covers all of the above, it's nice to work with, and it’s easier to install than many of the modern man-made installations.
Just by adding the right insulation to your property will make a vast difference to its insulating and heat retaining properties. It will be more air tight - you’ll be aiming to make it as air tight as possible in order to retain as much heat as possible - and that's achieved with the breather layers and vapour control layers.
But doing that in itself can lead to condensation and black mould issues unless you incorporate the correct ventilation system. A good ventilation system will allow you to remove the stale moist air that builds-up in a home from showering, cooking, drying clothes etc. and importantly without losing the valuable heat.
Your choice of ventilation systems will come down to a combination of your budget, and whether or not it will be feasible to install a full mechanical ventilation and heat recovery (MVHR) system or not. These systems are best fitted at the new-build or full renovation stage as they are pretty much integral to the property. But there are also other methods available short of these full systems, including positive input ventilators, passive stack ventilation and the simple good old trickle vents and extractor fans.
Extractor fans in kitchens and bathrooms, where the bulk of steam is produced in a property, can be of the automatic type – the humidity sensing fan which will keep the air clear of the condensation producing steam.
Whether you’re building your property from scratch or refurbishing an existing property, as part of your energy efficient home design you’re also going to need to consider heating and cooling - yes, we’re in the UK, but cooling is also important.
The heating side is something we’re all used to thinking about, but once your property is super insulated and properly ventilated it won’t need as much heat in order to maintain a comfortable temperature – it will also save your tenants a lot on their heating bills, which they’re bound to thank you for!
The house will consume less gas, oil or electricity etc. depending on what you have chosen to heat your property with. An architect should be able to calculate the heat load for your property in order to get the right size of heat source, a boiler for example.
Cooling is the bit we’re less used to considering in the UK. But it’s essential that you think this through carefully. In the winter you’ll not have any cooling issues but, in the summer, your super insulated home runs the risk of the sun shining directly on windows and large glass patio doors which will generate a lot of heat in the rooms, making the house very uncomfortable.
Some modern man made insulation materials will allow the heat from the sun to pass through them very quickly. To get round this a dense insulation material such as wood fibre will slow the heat transmission from minutes to hours. Plus, it's easier to work with and doesn't contain any nasty chemicals.
It’s also worth considering heat reflective glass when fitting or replacing south-facing windows and patio doors. These considerably reduce the amount of heat passing through them in direct sunlight and will make occupation in hot weather much more tolerable.
So, you can now see how each aspect of your energy efficiency project comes together and can impact on something else. If there are a lot of large south-facing windows or glass doors they’ll do a great job of heating your home in the winter but the same effect will likely cause it to overheat in the summer unless you have that reflective glass.
Another way of avoiding this problem is to fit shades over the windows that allow the low sun in the winter to heat the rooms, but when the sun is high in the sky in summer its rays are shaded from the glass and the rooms, keeping them cooler.
It's very easy to get caught up in the latest and greatest gadgets to improve the efficiency of your home, says Jeremy, but he advises discretion as it's very easy to spend huge amounts of money on technology to try and reduce heating costs in a property when it's actually more important to get the basics right.
If you can achieve the energy efficiencies by super engineering and getting your ventilation correct, you will be able to install a smaller boiler as the peak demand will be less and will require less of the "technologies" that are out there, waiting to take your money.
That said, there are still some technologies that are worth considering: solar, photovoltaic panels, backup battery systems, smart thermostatic radiator valves, etc. to name just a few.
But the key issues - insulation and ventilation – get them right and if you go for some of these other technologies, for example you'll be able to get away with a smaller PV array and a smaller battery pack, which will cost you a lot less!
Heat reflective glass has already been mentioned, but unless you live in a listed building or a conservation area, your choice of glazing will probably be a personal one. You should go for the best glazing you can afford and preferably triple glazed, if possible.
In older buildings, you may not be able to get permission to do this, and you may be restricted to secondary glazing, in which case, the more you spend, typically the better results will be.
It’s all too easy to just let your architect or builder get on with the job and not pay too much attention to when you are really after in terms of heat retention and energy efficiency. You need to take the initiative with them and do some research and monitor yourself.
You should make a list of your priorities in descending order, (1) being the most important, such as:
An architect and many builders will have more information to help you make decisions regarding the systems, materials and technologies which can be used within the build/refurbishment. Otherwise, do some reading / research and look into different manufacturers’ products – the Internet is a good place to start. Here are some types to consider at an early stage of new-build or renovation:
Try to imagine yourself living in each room of the house, using them as your tenants normally would. For example:
Once you get initial drawings or a refurb plan, make scaled cutouts of furniture in each room and visualise where lighting, sockets etc. will need to go. The more you can get right now the less chance there’ll be that you need to do restorative work or disappoint your tenants because things don’t work for them.
When you need to make changes during construction or refurbishment, it WILL cost you more money and time. Once you’ve given these priorities to your architect or builder it’ll be up to them to work out the less glamorous bits of your energy efficient requirements, but don’t leave it at that: monitor like a hawk what’s going on. Many of these items are hidden for view once installed so you don’t want corners being cut on installation.
An energy efficient house will not only meet the latest and future energy efficiency standards laid down by the authorities, it will be comfortable and inexpensive to live in. What’s more, getting it right from square one isn’t as complicated as you may think. Provided you do enough initial research at the design phase, you should get it right with the least possible cost.
You will find some useful resources here -
Tags:
Comments