Chapter 15: Sustainability


In this era of global warming, the greenhouse effect, climate change and high energy bills, it really is vital that we do everything we can to reduce our energy use and our carbon footprint.

Not only does it benefit the environment, but making your home more energy efficient can have huge benefits for you by reducing heating and water bills, and even adding to the value of your home.

Energy Performance Certificates

The Energy Performance Certificate (EPC) provides information on the energy efficiency of your home, giving a standard energy and carbon emission efficiency grade from A to G, where A is the most efficient. It also lists improvements you could make, costs, savings per year if improvements are done and what effect that would have on your grade.

Your EPC can help you cut your energy bills which could increase the value of your property.

Microgeneration Certificate Scheme

The Microgeneration Certification Scheme (MCS) gives an independent certification of microgeneration (renewable energy systems) products and services to consistent standards. Products and installers have to be certified to carry the MCS ‘mark’, and installers need to sign up to a code of practice in line with the Office of Fair Trading’s Consumer Code of Approval Scheme.

There are a range of products on offer which reduce the cost of energy and provide energy from natural resources.

For further information, visit the website

T-Zero Web Tool

T-ZERO is a website tool which can help homeowners upgrade their home to increase energy efficiency and reduce its carbon emissions.

You can put the details of your house into the tool and the tool will recommend what you can do to reduce your carbon footprint, and recommend packages of work to be done. Once you’ve picked the package you want, T-ZERO can introduce you to suppliers and you can get a quotation through the site.

The web tool can be accessed at

NHBC Foundation

The NHBC, in partnership with the BRE Trust, is a research and development foundation for sharing technology, knowledge and best practices.

There are many papers on the site focusing on new, cleaner, more energy efficient technologies and sustainability, looking at the energy implications of design, materials and services systems.

For further information and to access all the papers published by the Foundation, see the website

Energy & Water Efficiency

From benefiting the environment to saving on your water and energy bills, there are plenty of things you can do to improve your home’s efficiency, and it’s not just about fitting insulation and taking showers instead of baths. Read on for more ideas than you can shake a low-flow shower head at!

Cavity Wall Insulation
In cavity wall insulation an insulating material, such as mineral wool, is added by drilling holes to a set pattern into the wall, and then injecting the material into the cavity through the holes.

This is the easiest and cheapest type of wall insulation, and a very cost-effective energy saving measure.

Solid Wall Insulation
External wall insulation is more effective than internal insulation, helping to both retain heat in the winter and keep cool in the summer, as well as reduce internal condensation and mould growth, but can be more expensive and reduce the size of your room. You will also need to redecorate.

Roof Insulation
Around 25% of heat lost from an uninsulated home goes through the roof, but you can easily install roof insulation, and it’s even more easy when you’re already rejigging the roof for your loft conversion.

For a warm roof, you could use batts of mineral or glass wool insulation, held in place by the battens, or you could fit polystyrene slabs.

We’ve included more details on types of insulation in chapter 8.

Floor Insulation
A common way to fit floor insulation is by lifting floorboards and laying mineral wool insulation, supported by netting between the joists, or by fitting rigid boards between the joists supported on battens.

Floor insulation is very effective but floorboards will need to be taken up, as well as carpet or flooring, so it can be a big and messy job. It’s usually only cost effective if you’re having refurbishment work done.

Windows & Doors
There are three main areas where you might fit windows or doors in your new loft conversion. You might have new openings in the gable walls, new dormers or roof windows.

You’ll also need to have an escape window for fire and consider whether any glass needs to be safety glass, such as any glazing along the lines of your staircase.

Draught Proofing
Air leakage is a fundamental problem, even with new housing and draughts can cause discomfort, as well as adding to your energy bills.

Draught proofing can reduce your bills by stopping heat escaping from your house and preventing cold air from coming in.

You can fit various types of draught proofing, such as foams, sealants, strips and shaped rubber or plastic.

Boilers & Controls
A replacement boiler can make a huge difference in the energy efficiency of your house and save up to 25–35% on heating bills.

Condensing boilers are cheaper to run as they recover energy from waste heat, which is usually lost through the flue of conventional boilers.

Good controls should be fitted, such as a hot water tank thermostat, room thermostats, and thermostatic radiator valves.

Lighting & Appliances
Switching to low energy light bulbs is one of the easiest things you can do to save money, and you can also install low energy light fittings, which will only accept low energy bulbs.

Running your fridge-freezer, the tumble dryer and the washing machine can add quite a percentage to your energy bill, and fridges and freezers account for 20% of electricity used in the average UK home, so it makes sense to fit A-rated appliances.

Low-Flush Toilets
Toilet flushing accounts for around one third of the water used in the home, and one toilet flush with an older style toilet uses 14 litres of water, whereas new dual flush models use as little as 2.6 litres per flush, so fitting a low-flush toilet can reduce your water bill if you are on a meter.

All new toilets in the home must now have a flush of no more than 6 litres.

Low-Flow Taps
Saving water can reduce your water bill, reduce your energy bills, and reduce carbon dioxide emissions by using less energy to pump, heat and treat the water.

You can fit low flow taps to your kitchen and bathroom sinks, click point taps are great for the kitchen sink and regulated or aerated flow taps are better for the sink in your bathroom.

Low-Flow Showers
The average shower in the UK last 8 minutes and uses around 60 litres of water. Even if you don’t have a water meter, you still need to pay for heating the water so, obviously, using less water will help to reduce your energy bills.

Adding a water saving showerhead is a quick way to reduce water usage, and showers should have a flow rate of 9 litres per minute or less.

Small or Standard Baths
If you fit a smaller bath, it will take less water to fill it, which again helps with your heating bill.

A standard bath in the UK is 1700mm long x 700mm wide and a smaller bath does make a difference, at only 1400mm long.

Obviously, this may be something you’ll have to consider anyway if you don’t have a huge amount of space in your loft conversion.

External Water Use
A water butt could help you collect around 5,000 litres of rainwater a year and having a water butt could also help to reduce surface water flooding.

Acid-loving plants and pot plants prefer rainwater and using the water out of your water butt instead of treated drinking water is better for your garden, local wildlife and the environment.

Grey Water Recycling
Grey water is the waste water produced from baths, showers, washing machines, and washbasins, though water from toilets isn’t considered to be greywater. The water is collected, treated and then reused in toilets and for outdoor use. It may still contain some soap and detergent, but is clean enough for non-potable uses.

Rainwater Harvesting
A Rainwater Harvesting Systems (RHS) tank can easily filter and store up to 6,500 litres of clean water, and new technology means an RHS can now be plumbed into your home’s existing pipework and the rainwater used to flush toilets and wash clothes, which could reduce your water use by as much as 40%, according to the Rainwater Harvesting Association.

Green Roofs
While you are having your loft converted, you could consider installing a green roof at the same time. Doing so can make a big difference to your carbon footprint and get a better EPC grade for your home, as they have excellent insulation properties, which give you warmth in the winter and cooling in the summer.

You will need to consider the type of green roof as, depending on which one you choose, you may have to look at the structure of your building to see if it can be supported.

We’ve probably given you a great deal to think about in this guide and, although it’s hopefully a bit less technical now, you may still have questions or even want to get started with a free estimate for your own loft conversion, so give our friendly experts a call on 0800 046 1995 or complete our online free estimate to get started!