Ten top tips for major energy saving home improvements
Posted by Jonathan Atkinson on 6 February 2015 at 8:12 am
With a goal of reducing costs and carbon emissions by 80%, Carbon Co-op ran a 'deep retrofit' project for nine of our owner-occupier members last year. The Community Green Deal project was funded by DECC and run as a pilot.
Work on the first phase of houses took place last year, and we are monitoring and evaluating it so that we learn from the pilot. We're keen to see how close we get to the 80% goal in reality, and what ther reasons are for gaps in performance.
If you're thinking of carrying out similar works on your home, here are some of the lessons we learned.
1. Set out your priorities from the start
An understanding of your priorities will assist in the delivery of the project. Some people have a budget to work to, others may be working to a date or deadline, but for most high quality in terms of built performance reduced carbon emissions and fuel bills is key – as well as factors like aesthetics and comfort. Understanding this and articulating it for yourself and your team will assist decisions later and inform you on where you can compromise and where you shouldn’t if you want to meet your priorities. And compromises somewhere along the way will almost always be necessary!
2. Assess current energy performance
Most people we work with say the same things, 'Where do I start, what do I do first?' A thorough energy performance assessment will help you understand where most heat is lost in your home and where the 'big ticket' improvements lie. Some people have the skills to self assess, others will need to employ an assessor, but beware, Green Deal Assessments are crude and imprecise so look out for more comprehensive services!
3. Get the right advisors and contractors for the job
You may have all the skills necessary for a whole house retrofit - but it's very unlikely! Having surveyors, assessors, engineers or architects on board from the start might mean additional cost and time but will be worth it in the long run and will ultimately save money, avoiding mistakes and lost time. What about the things you've not thought of - have you got a ventilation strategy in place for example?
4. Make sure the contractual relationships are clear (and in writing!)
Understanding your priorities and putting together the right team will assist you in deciding how to contract the work. There are a variety of options but a traditional contract or a design and build contract are the most common in construction as a whole. In the traditional contract the design work is done upfront by a consultant (an architect, engineer or building surveyor) and a builder delivers the work set out in the contract documents. In a Design and Build contract, you specify your desired outcomes and the builder covers the design work to achieve these. It's important to understand the pros and cons of each form – where the risks lie in terms of quality, cost and time.
5. Thoroughly check out potential contractors
Sadly, the retrofit business is in a very embryonic state, and as a result it's hard to find the right contractor. Do plenty of research on this, for example by contacting people within SuperHomes or Open Green Homes networks, or ask specialist suppliers and manufacturers for recommendations (some will have a list of approved installers). [You can also look on YouGen - Ed] Always ask contractors to provide contact details of past customers, contact these people and if possible visit them to see the work that was done. You may also want to do background checks at Companies House to check their credit history.
6. Segment your works in to packages
With whole house works it's usually possible to segment works in to packages in terms of how the improvements will be carried out; some parts might be DIY, others may be delivered by a jobbing builder, others require specialist contractors. Alternatively, works can be packaged up on the basis of cost, i.e. “we'll spend £20,000 in total and if part 1 of the job over-runs we'll drop part 2”. Segmenting helps later procurement and budgeting decisions – and means you can manage the amount of risk you take on at once. Take your time, a full retrofit could be staged over many years as and when funds become available, if that’s what best suits your circumstances.
8. Expect disruption and plan accordingly
Whole house retrofit is by definition disruptive. You should expect dust, dirt, and contractors to be tramping in and out of your home. Don't underestimate how stressful it is to be without a clean, quiet, space to relax. Consider moving out at the most disruptive times and discuss protective materials for carpets, furniture etc with contractors before they start work!.
9. Have a plan for monitoring and evaluation
It's important to evaluate how effective the work carried out has been. Heat cameras, smoke pencils, air pressure tests, energy bills, energy monitors and humidity sensors can all be used in this process, and if you can compare this data to pre-retrofit figures all the better. If you’ve packaged up different parts of the work, this might help you decide what to do next, and where to focus your efforts.
10. Team up with others and go for it!
Don't be put off! With careful pre-planning and realistic expectations you can transform your home and make it a comfortable, climate-safe environment for many years ahead. There's also no need to do it alone, use organisations like Carbon Co-op within the Green Open Homes Network or Community Energy England to find other people who have done it or who are going through it to share experiences, contacts and good advice - you may even be able to procure works together as we have in Community Green Deal.
How the Community Green Deal worked
Assessments and design work was carried out by technical partners, URBED to deliver 'whole house retrofits' - multiple measures, installed as a complimentary, holistic system, bespoke to each household.
Improvements included wood fibre internal and external insulation, triple glazed windows, floor insulation, solar panels, new boilers and demand controlled passive stack ventilation systems (see full list below). The average price came in at around £40,000 per home including prelims, supply and construction – it seems like a lot, but it’s cheap in comparison to many previous retrofit projects of a similar standard.
Full list of improvement specifications
- External wall insulation (as appropriate often at side and rear of property), example specification: 180mm thick Unger-Diffutherm woodfibre (for vapour permeability and all round sustainability)
- Internal wall insulation (as appropriate, often on front elevation), eg 125mm vapour permeable Unger-Diffutherm -woodfibre internal wall insulation
- Replacing existing windows with Eco-contract ULTRA triple-glazed timber windows from Green Building Store (U-value 0.79 W/m2K).
- Insulated timber external doors.
- New gas A-rated condensing Vaillant combi boilers
- Aereco demand controlled passive stack ventilation systems to improve and stabilise internal air quality while minimising energy use
- Loft insulation top up to 400mm
- Floor insulation: 200mm wood fibre insulation between joists
- Air tightness works
- High efficiency solar photovoltaic panels to generate electricity
- OpenEnergyMonitors - to track electricity usage, temperature and humidity
...and a variety of bespoke measures and details.
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About the author: Jonathan Atkinson is project manager at Carbon Co-op and manages a range of innovative projects demonstrating the effectiveness of collective action on climate change.
If you have a question about anything in the above blog, please ask it in the comments section below.
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