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Tag: Old House Eco Handbook

  • HPH289 : Retrofitting period properties – with Roger Hunt

    HPH289 : Retrofitting period properties – with Roger Hunt

    Author Roger Hunt explains why period properties need treating differently when it comes to achieving successful retrofit projects.

    Interview with Roger Hunt

    Roger Hunt co-authored Old House Handbook back in 2008, about repairing old buildings, at a time when retrofit was barely on the agenda. Not long after, people started to recognise the importance of retrofit and sustainability which led to their companion book, Old House Eco Handbook. It has since been updated with a second edition, incorporating new thinking on how to make buildings energy efficient, and the surge of new materials available that can make it happen.

    Not enough progress is being made

    Roger recalls attending a conference not long after Old House Handbook was published where, to meet targets, it was claimed that a city the size of Coventry would need to be retrofit every week.

    “We’re nowhere near that. We haven’t scraped the surface. We are so far behind in terms of retrofitting old buildings that there is absolutely no way we’re going to meet the targets we need to meet as far as I can see. And we can’t build new homes to solve the problem because we can’t build them quick enough; there isn’t the land to build them on. And the environmental impact of knocking all the old ones down to build new ones isn’t sustainable either.”

    Typical UK housing stock – Copyright Roger Hunt
    Copyright Roger Hunt
    Copyright Roger Hunt

    Pre and post-1919 buildings need treating differently

    Roger defines old buildings as being anything from medieval through to Victorian and Edwardian terraced houses. They were houses typically made from breathable materials, such as lime mortars, renders and plasters.

    Getting the retrofit techniques wrong in a breathable type of construction can store up problems for the future in terms of damp and condensation.

    It is important to make the distinction between those breathable buildings, and ones from around 1919 onwards, when construction methods changed to concrete and cement being used with a focus on keeping water out. Those buildings need to be treated differently, as getting the retrofit techniques wrong can store up problems for the future.

    Start with a plan for the whole building

    It might be that you won’t intend to do a full retrofit straight away, just elements of it to begin with and the rest spread over several years, but it’s important to think of your long term plan of everything that will need doing.

    For example, starting by draft-proofing all the windows and floors will cut down air movement within the house and cause a build up of condensation and poor air quality, if controlled ventilation isn’t considered. That might be achieved by controlled opening of windows, or a mechanical ventilation system.

    Using controlled ventilation – Copyright Roger Hunt
    Opening windows as a form of controlled ventilation – Copyright Roger Hunt

    Roger says that some sort of mechanical ventilation is almost inevitable, particularly for kitchens and bathrooms, but heat recovery systems don’t necessarily work well in old buildings.

    Reducing drafts is as important to comfort level as insulation

    Drafts actually make you feel colder than the building really is, so introducing secondary glazing or draft proofing around windows can make a big difference to comfort levels.

    Other uncontrolled ventilation can come from gaps in floorboards. If they can be plugged and a window opened when required then you can have controlled ventilation.

    Copyright Roger Hunt

    Buildings must be properly maintained

    Roger stresses that maintenance is particularly important for old buildings. Blocked gutters for example can lead to thermally inefficient wet walls, and a slipped roof tile can lead to leaks, rotten timbers and water coming through ceilings. The repair job is going to be costly and a lot less sustainable than just maintaining the building properly.

    Copyright Roger Hunt

    Reduce energy use within the house

    Before even thinking about how to heat or light the home, you should be thinking about a fabric first approach of how to insulate, cut drafts, and increase daylight. From there you could incorporate solar arrays or air and ground source heat pumps. The heat pumps won’t work so well if it is a leaky building, so these all need to be considered as part of the bigger project.

    “You have to think of the best solution for heating combined with all the other things you’re doing. So, an air source heat pump is not necessarily going to be the solution until you have tackled some of the other issues with the building.”

    Simple things that can be achieved quickly with an instant impact include changing high energy bulbs to LEDs and putting in loft insulation.

    Copyright Roger Hunt
    Copyright Thermafleece

    EnerPHit projects can be incredibly successful

    With fairly disastrous consequences to getting it wrong, one way to have a successful outcome is to work towards the EnerPHit standard. This will probably mean employing an architect or other specialist with experience of what they’re doing. It might not be cheap or easy but will deliver on energy efficiency and comfort.

    There is a delicate balance between sustainability and retaining character

    A risk of coming in and doing a complete retrofit of an old building is that it can lose some of the character which makes us love them in the first place.

    “I’m passionate about trying to make buildings sustainable and cut our carbon but at the same time we’ve got to have places that are accessible, enjoyable and important to people.”

    Roger says it’s a complex subject as we have to embrace the value of the building in terms of beauty, aesthetics and our love for them, along with the monetary value.

    Take time to understand your building

    Roger’s tips for tackling a renovation of an old building are:

    • Don’t rush in. Live in an old building for a year, through each of the seasons, to really understand the damp and the light. That will also help with your interior decoration.
    • Don’t try and use modern materials that are incompatible with an old building. Particularly don’t use an insulating material that is going to stop your building from breathing.
    • Do your research, talk to people, go to events, look at products, don’t trust everything you read on the internet. Cross-reference everything to check that you have the right solution. What might be right for one building isn’t necessarily right for another, even in the same terrace.

    Find out more

    Visit Roger’s Huntwriter website

    Transcript

    Download a transcript of the interview with Roger Hunt.

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  • HPH010 : Can You Damage an Old House When Making it Energy Efficient? – with Roger Hunt

    HPH010 : Can You Damage an Old House When Making it Energy Efficient? – with Roger Hunt

    Roger Hunt explains how to make a period property energy efficient without damaging the building or creating problems for yourself in the future. Also House Planning Help gets its first guest blogger, Paul Mallion from Conker Conservation.

     

    Interview with Roger Hunt

    Co-author of the Old House Handbook Roger Hunt has just finished work on a companion volume called the Old House Eco Handbook (which will be available in March 2013). Although the first book was written in 2008, Roger says environmental issues and energy efficiency have now become much more pressing and so the time is right to focus on how this can be achieved for old houses.

     

    An Old Building is a Solid Wall Building

    The Old House Eco Handbook is in association with The Society for the Protection of Ancient Buildings. If you own a period property that was constructed anywhere from the Medieval era to the Edwardian period, then this book aims to help you. Roger points out that after the Edwardian period building technology started to change and move away from solid walls to cavity walls. Lime-based products became less popular while the use of cement-based materials increased.

     

    Lime-Based Materials Work in a Very Different Way to Cement-Based Materials

    In an old building it’s not about keeping the water out, as the walls absorb moisture. Both the inside and outside walls are constantly absorbing moisture or allowing it to evaporate out. Modern cement-based materials try to keep water out of the building by using impermeable layers. Mixing the two methods causes problems.

     

    Old Buildings are an Essential Part of Our Landscape

    Roger believes that old buildings are not only part of the landscape but part of our communities. Getting rid of them will break up communities and destroy landscapes. Towns and villages have grown very organically through the years with little accretions, creating much-loved wibbly-wobbly streetscapes. In his opinion removing the old to make way for the new would be a bad move, not to mention all the embodied carbon and historic detailing that would be lost.

     

    Take a Holistic Approach to Energy Efficiency

    View your house as a whole and don’t just do one thing in isolation (like putting solar panels on the roof). Take time to consider all the things you could do. For example, loft insulation can make a big difference and it’s a relatively simple project. Draughts can make a building feel colder than it is, so deal with those sorts of things.

     

    Keep Original Timber Windows

    Roger illustrates the point by suggesting you wouldn’t throw out an Edwardian chair because it had a damaged leg – you would get it repaired. In the same way if you have original windows you should not be looking to replace them with double glazing. Instead get them repaired and also draught-proofed at the same time so that they perform better, too.

     

    Simple Measures Can Often Make a Big Difference

    • Draw curtains and blinds to make a room warmer.
    • Put a wooden flap over the letterbox to stop the draughts coming in.
    • Use a fabric sausage to stop draughts coming under doors.

     

    Passivhaus is an Excellent Standard for New Builds

    Roger is a great believer in Passivhaus and he thinks that it can really produce high performing houses.

     

    Bringing an Old Building up to Passivhaus Standard is Quite an Invasive Process

    Roger has seen retrofit projects himself and he agrees that they have reached a high level of energy efficiency. However, the problem is the loss of character and historic detail of the building. These are the very features that make these buildings desirable in the first place. A Passivhaus retrofit means losing a lot of the original fabric of the building and balanced with the carbon, Roger is not sure whether it adds up. Some of those materials are irreplaceable once pulled out.

     

    No Single Solution Works For Every Building

    The holistic approach is about insulation and finding the right energy generation methods to suit the building. If you’re in a very old leaky building in the countryside a biomass boiler might be the answer. If you’re in a town, an air source heat pump might be the answer. Every building is different.

     

    A Passivhaus Retrofit Would be More Appropriate if a House Had Already Lost its Original Features

    When Ben explains that he didn’t notice any loss of character in a recent Victorian Passivhaus project he saw, Roger stresses that he is not against a Passivhaus renovation in the right circumstances. However, where original features exist such as dado rails, skirting boards, cornices and windows, he believes this is a lot to lose.

     

    Retrofitting Old Houses is Something We’re Still Learning About

    This is not something that is set in stone and different people have different ideas on how it should be done. Putting together the Old House Eco Handbook has involved a lot of research to understand the current thinking. Roger believes this thinking will evolve as better ways of doing things are discovered. There is a fear that what is being done to many buildings will have to be ripped out in 10 or 15 years because of damp problems, etc. This would clearly not have a positive impact on the environment either.

     

    Don’t Slap on Wall Insulation Without Understanding the Science

    Although this book is offering solutions, it’s also saying in many cases don’t do anything. This does not just apply to you but to the wider community. So tackle all the other simple measures first to make the house warm and air tight, and perhaps leave wall insulation for a later project.  Balance the cost versus the gains, bearing in mind the potential risks of trapping moisture in the wall.

     

    Insulating Will Lead to Loss of Features

    Whether you insulate on the outside or inside of an old building you will lose features. While it’s easier to insulate the outside of a building, insulating on the inside of the building is generally considered to have less aesthetic impact. There is also a risk of interstitial condensation occurring where the warm air meets the cold surface and dampness occurs. The science of this is not fully understood. This can cause timber in the wall, for example, to become rotten.

     

    Moisture Levels Are Being Monitored

    A lot of test projects involving wall insulation are underway at the moment. Wireless moisture sensors are being embedded in the building materials to see whether there are really any problems. This is something we will only find out over time.

     

    Think Beyond The House to The Neighbourhood

    Good design looks beyond the house to the neighbourhood. Roger uses an example of why a cluster of 12 houses might be a good idea, because it would be possible to for you to know all of your neighbours. He also says simple things like a bench out on the street or low garden fences to encourage interaction allow for good sustainable development.

     

    Good Modern Design Needs to Meet Regional Variation

    As an advocate of modern architecture, Roger likes simple white rendered buildings. However, he is aware that it would be a bit boring if they were everywhere. The character of a place is down to the variety of materials used there. In the past houses would be constructed with materials that were available locally and Roger would like to see modern design adapted to reflect this regional identity.

     

    Grade 1 and Grade 2* Listed Buildings are Difficult to Make Energy Efficient

    Roger is adamant that we need to improve the energy efficiency of our buildings. He does, however, think that buildings of historical significance are difficult to deal with and suggests that perhaps these buildings should remain as they are. It is the bulk of the housing stock that needs to be addressed.

     

    Classic Cars Still Exist as Classic Cars

    Roger talks about a picture in the Old House Eco Handbook (affiliate link), where a Morris Minor is parked in front of an Edwardian House. While cars have changed hugely in terms of energy efficiency, it does not mean that the classic cars have been updated with today’s technology.

     

    Everything is a Balance

    While future generations may love us for making old houses more energy efficient they may hate us if we destroy what was good about them.

     

    Check out Roger Hunt’s Blog

     

    Transcript

    Download a transcript of the interview with Roger Hunt.

     

    First Guest Blogger on House Planning Help

    We’re always trying to create more great content and one way of doing that is with the help of a few carefully chosen experts. Paul Mallion from Conker Conservation has become the first person to write a blog for us and we are very grateful to him. Read his article about why white paint is potentially a colour you don’t want to use.

     

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