COVID-19, A Sustainable and Resourceful Building Project

We are now into the fifth week of the COVID-19 lock-down and the end still feels a long way away.

Along with others in our street, around the country, and all over the world, I have been clapping for the healthcare workers, first responders, hospital cleaners, service-industry employees, and all the other dedicated people who are on the frontlines of the pandemic. All these amazing people are risking their lives every day to save people from the virus wreaking havoc around the world. I respect and applaud all of them.

Builders are doing their bit

There are others in the country, in the construction industry, not on the front line and not putting their lives at risk, but who are doing their bit. They are doing their bit to keep the economy going and ensuring that their client’s homes are not left insecure, unsafe, and unfinished.

The builder who drove miles to pick up some ‘leftover’ plasterboard sheets to finish off a job. Another who spent a couple of hours digging up some waste sand from a back garden so he could make a chimney stack watertight. Or the builders who order materials on ‘click and collect’ and patiently wait in the queue to pick up their materials to finish off their client’s job. This shows real commitment; to keeping their company going, to their clients, and to their employees whom otherwise would be without work.
Operating like this is time-consuming and can be frustrating but it keeps things going and it is being resourceful. As one builder (Drew) said to me “his Dad always kept ‘leftover materials’ just in case they were needed. Drew developed this ‘savings’ habit and with some material now like ‘gold dust’ all the bits and piece hoarded in his garage are now becoming very useful.”

Resourcefulness at home

As for me, well I have one new job (a detached uninhabited garage), and I am finishing off existing jobs where I can but otherwise, work has ‘fallen off a cliff’. Clients are reluctant to commit spending money until they can be more certain of their future.
The allotment has never looked so good and we are really on top of things there. We have re-built the compost heaps from pallets found on the street and made a new gate that’s been on the list for some time. The new gate has a Sweet Chestnut frame made from leftover bits of decking and an infill made from old pallets. All these materials were just ‘lying around’.

Sustainable Sweet Chestnut

Sweet Chestnut is the only other English hardwood (Oak is the other one) that has a high level of natural tannin or Tannic acid. The tannin makes the timber more durable and is perfect for decking or external cladding.
Sweet Chestnut is also really sustainable. All over southern Britain, you can still find Sweet Chestnut coppices. Coppicing (cutting the 80-100 year old Sweet Chestnut every 15 years or so) is a harvest, which encourages new timber growth. It is also hugely beneficial to wildlife and a host of plants, moths, and insects. Bluebells run riot after fresh cutting and, combined with mature ‘standards’ (trees which are left), chestnut coppicing produces a wonderful woodscape, it is really sustainable and is superb woodland husbandry.

Tackling climate change must be part of the COVID-19 solution

There are many devastating personal impacts from COVID-19 and I would not want to downplay these but maybe our experiences will make us think more about the environment. I rejoice about the lack of cars on the road, the cleaner feel to the air, the absence of vapour trails from planes, and the quiet. Indeed, only yesterday the BBC reported that “Tackling climate change must be woven into the solution to the Covid-19 economic crisis, the UK will tell [other] governments next week.”

Reusing surplus building materials

In addition to thinking about the impact of our homes, (I think every new building should by law be required to be built to Passive Haus standards) how about doing something positive about all the left-over building materials (not in Drew’s garage) that are sent to landfill.
A quick Google search reveals many organisations who specialise in re-using building materials. Enviromate is just one of these and they state that the UK building industry used 240 million tonnes of material and products every year, nearly 30% is wasted, and 13% is new and never used. This is £1.5 billion work of reusable surplus building materials that enter the waste stream and landfill every year in the UK!

So, when things do get going again and you’re lining up your builder to start work, think about and ask them about waste, sustainability, and reusing materials. It might save you some money and it would certainly be good for the world and the environment.

For details of my other blogs please check out my website:

Please note this is a guide and is not a definitive source of technical and/or legal information.

MM – COVID-19, A Sustainable and Resourceful Building Project – V3 – 28 04 2020

Check-out Your Ground Floors

The next step in my maintenance and retrofitting journey is to investigate the state and condition of my ground floors i.e. those floors and walls that are in close contact with the ground.

Checking your Ground Floors

Solid floors are benign but can be cold and damp. If you have timber floors at ground level checking their condition is critical. Damp rises up from the ground into the masonry, rain wets the exterior walls and moisture from the inside of your home all add to the water within the fabric of your building. Timber at ground level or close to wet masonry is susceptible to getting wet. Damp timber will, over time rot. Wet timber in an unventilated or poorly ventilated floor void will rot. Wet rot can lead to dry rot.

Solid Ground Floors

If you think all or some of your ground floors are solid try the jump test. If it is a solid floor there will be no bounce when you jump up and down on it. Masonry and particularly concrete is pretty good at dealing with damp but without a barrier (commonly known as a DPC or damp proof course) damp will rise up into the masonry making any timber in contact with it damp. Damp walls will also add to humidity and moisture within your home.

Suspended Timber Ground Floors

Many of our homes are finished with carpets, tiles, laminate flooring or engineered wood and it can be difficult to determine whether the ground floor is suspended or solid. If like me you have the exposed original floorboards, the gaps between them and the draught coming up tells you that they are suspended.
If you don’t know, try the jump test. If you get some bounce this indicates the floor may be suspended but it could be a timber floor over a solid floor.
Is the floor warm or cold to the touch? A solid floor with ceramic tiles will feel cold but an engineered timber floor finish whether solid or suspended will feel warm so it can be difficult to tell.
Go outside and see if there are air bricks in the exterior walls, you should have them at the front, the side and the back. They are the best indicators that you have a suspended timber ground floor.
If you cannot find out, go to your neighbours and ask them. If you houses look the same it is likely the floors will be the same construction.

What’s the condition of your Suspended Timber Floors?

If you have air bricks in the exterior walls do you have them at the front, the back and at the side? You need this for adequate through ventilation.
Have the air bricks been covered over or blocked up by previous works? Is there excessive bounce or worse still, is part of the floor is dropping?
What about the smell? Damp rooms usually have a distinctive and easily recognisable smell.
Are the floorboards or skirting boards damp? Or to put it in technical terms, is the moisture content of the wood at a level where decay will start? At a moisture content of 20% or more wood will start to decay.
You can buy a basic ‘mini moisture meter’ for less than £15 from Tool Station– much less than dealing with an outbreak of dry-rot.

Moisture Content of Wood

Timber with a moisture content below 15% is generally consider to be safe.
Timber with a moisture content between 18-25% is at risk.
Timber with a moisture content above 25% is considered to be already decaying

We all tend to ignore parts of our home that we cannot see, preferring to spend money on visible illustrations of our taste and aspirations. We are all required to keep our cars in good condition, maybe a ‘home MOT’ looking at parts of our home that need maintenance would encourage us to focus on those areas we ignore. We should perhaps spend money on maintaining the essential fabric of our homes then consider the aesthetics and the fancy bits.

For details of my other blogs please check out my website:

Please note this is a guide and is not a definitive source of technical and/or legal information.

Retrofitting your Home

I have recently completed the AECB (Association of Environmental Conscious Builders) CarbonLite Retrofit course. This is an excellent online learning course targeted at architects, designer, and builders who want to understand the intricacies and details of retrofitting domestic homes.

This is the second in a series of blogs on maintenance and retrofitting where I share my journey and my thoughts with you.

What is Retrofitting?

Retrofitting is the addition of new technology or features to a building in order to improve its performance. This performance is usually measured by an improvement in energy efficiency and/or a decrease in energy demand.
The AECB advocates that an improvement in the health and comfort of the occupiers and in the state and condition of the house is an integral part of a good retrofit.

Why Retrofit our Homes?

For our part in preventing (or limiting) global warming Britain has a target to achieve zero carbon emissions from our homes by 2050. 80% of the existing housing stock will still be occupied in 2050 and on current projections, our houses will emit over 50% of greenhouse gases by this date.
Unless your home is about to fall down or is planned to be demolished it will still be occupied in 2050. Energy will be more expensive and global warming is projected to cause floods, droughts, heat waves and extreme weather events. These conditions will test the fabric and performance of our homes.

Why Maintain your Home?

Effective and timely maintenance and a well-planned retrofit go hand-in-hand. Before you do any improvements works to your property or build an extension or convert the loft or carry out a full retrofit it is a really good idea to check the existing fabric and structure are sound. If you don’t do this you could be covering up a disaster for the future – ‘a stitch in time saves nine’.

How do you Benefit?

A well planned and carefully executed retrofit will have a positive impact on your health, on your comfort, on the future condition of your house and on your wallet.
A good retrofit will have low energy bills, be warm & comfortable in the winter and cool & comfortable in hot weather. It will have good indoor air quality, be free of damp and mould and have low maintenance costs.
It will also increase the value of your home – what is there not to like?

Key principles of a Full Retrofit

The AECB has a number of key principles that are central to a successful low energy retrofit
The retrofit works have to be robust.
The new technology or features fitted must perform well under normal and abnormal conditions
The energy used to heat and power the building must be used more efficiently resulting in lower running costs for the occupants
The comfort for the occupants should increase in the summer and the winter
The retrofit should provide good indoor air quality and consistent temperatures.
The health of the occupants should improve
The retrofit should address long-term maintenance and health issues of the building
The condition of the building fabric will be preserved and enhanced, with reduced future maintenance costs

Typical Full Retrofit

Every property is different and all occupiers needs vary. There is not one typical example but a full retrofit usually includes;
Insulating the walls. Internally or externally. (Cavity wall insulation does not normally give sufficient improvement in the thermal performance of the walls)
Insulating the roof at loft, ceiling or rafter level
Insulating the ground floor (or floors adjacent to the ground)
Upgrading doors and windows (double or triple glazing)
Improving airtightness
The provision of continuous ventilation for the property (usually mechanical)
Installing a highly efficient boiler with well insulated hot water tank and pipes
Upgrading lighting and appliances

You retrofit could be carried out in one go or as a series of carefully planned and phased steps. You may want to combine retrofitting your home with other proposed works; an extension, a conversion, or refurbishment.

As I discovered when doing some budget costs, the expenditure in terms of the initial investment to carry a full retrofit on my house will be quite significant. So, how do I move things forward? (See next few blogs)

For more details of my work please check out my website:

Low energy/sustainability

Please note this is a guide and is not a definitive source of technical &/or legal information.

Clean out the Gutters

Did you miss National Maintenance week, which ran from 17th to 24th November? I did too. The Society for the Preservation of Ancient Buildings (SPAB) runs a National Maintenance week every year. The SPAB week focusses on older buildings but much of what they say can be applied to your home. Maintenance is often low on the list of work to do to our homes. We all want to extend, convert and improve rather than protect what we’ve got. Results of the English House Survey 2015-16 show that 18% of owner-occupied homes failed to meet the Decent Homes Standard and 3% have damp problems.

Checking your gutters & gulleys

The SPAB maintenance week finished with National Gutters day. Next time it rains hard put on your wellies and a waterproof, go outside and have a look at your gutters and downpipes. Is there water streaming down the exterior walls or are the gutters doing their job? Inspect the gulleys at the bottom of the downpipes. Is the rainwater flowing away freely or is the gulley overflowing and potentially adding to damp in your house?

At this time of year gutters and gulleys can be blocked by leaves. If you have leaves in your gutters and gulleys, vegetation growing in the hopper heads or water streaming down the walls you really need to fix it.

Internal Damp

Whilst you’re checking, are there any damp patches inside your house? If you have water streaming down the outside walls there is likely to be a corresponding damp patch inside. Check around chimney breasts. An open chimney can cause falling damp – rainwater entering the chimney and wetting the walls below. Alternatively, the pointing or flashing on the chimney could have failed.

Check the Loft

If you can get into the loft can you see any signed of water penetration? Dampness to the chimney breast may be more obvious. Can you see light through the roof? If you can this is a sure sign some tiles have failed and that your roof is pretty old (newer roof will have a waterproof membrane under the tiles).

Symptoms and Signs

Mould has a distinct smell, we all know the aroma that hits us as we walk into a damp basement. Wet walls are often a different colour from the surrounding paintwork. Condensation on internal walls, often in the bathroom or other hot damp rooms, is indicated by black mould. Mould spores are bad for your health. Low-level moisture, possibly caused by rising damp, will cause emulsion paint to bubble and flake off.

Why basic maintenance is essential

Wet walls and structure damage the fabric of your home, they are bad for your health and leaving a damp problem will cost you more money in the longer term. High humidity in your home can lead to a dust mite proliferation, which causes asthma. Poor ventilation can cause a build-up of chemical compounds and /or mould spores, which can result in repository problems.

A damp free and well-maintained house is a healthier and more comfortable house. If you are planning to build an extension, convert your loft, renovate or carry out retrofit measures, ensuring your home is well maintained and damp free should be one of the first steps in this process.

For details of other blogs please check out my website:

Please note this is a guide and is not a definitive source of technical & legal information.

Draft proofing a suspended timber floor

If insulating under a suspended timber floor is not possible, how can you stop the drafts between the floor boards?

Looking on the Web is a great way to research the best way of doing something. Caramel Quin wrote a great blog some time ago looking at ways to draft-proof stripped wooden floors.

Some timber and floor boarding companies had good blogs on the ‘filling the ‘gaps’ but many are for where you have not yet sanded the floor.

I thought seriously about using wedge-shaped pine slivers they are possibly the best and the most ‘green’ solution but I didn’t want to sand the floor again.

I needed to eliminate the draft but I wanted to retain the look of the golden pine boards broken by dark lines, which meant retaining the gaps. This stance eliminated using any kind of filler option, which can often fill both the gap and half the floor board.

Having considered all the options I opted for StopGap . It is thin V-shaped plastic on a roll that you push into the gap, down to the joist level and it opens out to fill the gap. It can be used to fill 1-8mm gaps in both floor boards and skirting boards. If you are going to re-varnish the floor this needs to be done before fitting the StopGap.  To ensure the StopGap works as efficiently as possible the gap between the floorboards need to be free from debris and any drips of old varnish cleaned off the sides of the floor boards.

I wanted to make the floor as draft proof as possible so to finish the floor I ran a strip of painted timber beading around the base of the skirting board and sealed this with an acrylic interior frame sealant.

The result; the ground floor is definitely less drafty and the room feels noticeably warmer.  The ‘under the floors board’ insulation option would have been better in terms of heat loss but it would have cost over £1,000. So I have stopped the drafts, kept my golden pine floor boards (some of which I have covered with rugs to give that real feeling of warmth) and the materials cost less than £150.

Insulating a suspended timber floor

My next task was to insulate the suspended timber ground floor.

I calculated that the gaps between my floor boards was equivalent to a hole 800mm by 800mm, no wonder it felt drafty. The floor boards on the ground floor are the original ‘pine’ boards, a beautiful golden colour. I wanted to retain them as a feature of the house so the only option was to insulate underneath them. The two ways to achieve this were either to lift all the boards and insert the insulation from above or get under the floor and insert the insulation from below. The floor was fixed firmly, it had been sanded and varnished already and lifting all the floorboards would have caused a lot of breakages and require re-sanding. The only option was to insulate and draft proof from underneath.

I removed a couple of boards in the hall, donned a boiler suit, goggles and face mask and squeezed under the floor – I could just move around, so it may be possible.

I now had to determine exactly what I needed to do. The Web has a number of good links covering insulating under a timber floor.–insulating-suspended-timber-floors.html

The aim is maximum insulation between the floor joists, using a fibrous insulation material that takes up the imperfections in the timber and that minimises the air movement around the insulation. The other objective is to stop the movement of air through the insulation and into the room but allow water vapour that may build up to escape. In addition; the insulation should not come into contact with any masonry walls but the gap between the joists and the foundation walls (usually about 50mm) needs to insulated and made draft proof, the air bricks from the outside need to be kept clear, cold water and central heating pipes below the insulation level need to be insulated (the void below the insulation will be much colder) and any electrical cables need to be prevented from overheating and kept free of insulation.

I needed to establish categorically if I could do all of this from underneath. There is a 400mm space between the bottom of the joists and the ground level but the joists rest on 100mm timbers so the working height is 300mm. I had to be able to crawl around underneath the floor for several hours completing the insulation and draft proofing work. I donned my boiler suit, goggles and face mask and after ten minutes established that 300mm was not sufficient room to do what was required – back to square one.

Passivhaus: German engineering for greener homes

Extending the Passivhaus methodology to all

I have studied to be a Passivhaus Designer. Whilst I am itching to get involved with my first Passivhaus I am very interested in the lessons we can learn from the methodology and how I can use this to the benefit of jobs where I’m not designing to the Passivhaus standard.

What is Passivhaus?

Passivhaus is a design and build methodology used to produce low-energy, superbly comfortable buildings. It was pioneered by German physicist Wolfgang Feist . In simple terms the high level of insulation, the super air tightness of the building and the rigorous attention to detail means that the heating demands can be as little as 10% of the heating required in a comparable building built to current UK standards.

There are thousands of Passivhaus on the continent, but in the UK there are only 100 or so newly built Passivhaus homes and a handful of retro-fits, which are existing buildings that have been upgraded to the Passivhaus standard. Passivhaus is a relatively new concept in the UK and build costs are said to be 10 to 15% higher than traditional build costs.

What can we learn from the Passivhaus methodology?

1.   More rigorous energy assessment

Passivhaus uses a planning/design tool that pulls together all the components of the building, enabling the designer to adjust the type, performance and/or cost of the components to achieve the optimum energy use of the building. It’s the most rigorous, accurate and detailed energy assessment tool  I have ever used and its wider use would significantly benefit any building job.

2.   Closer attention to detail and air tightness

A large part of the success of a low-energy home is to have well thought-through and detailed designs of the elements of the building where heat is lost. Passivhaus requires the architect to produce details for the junctions and for the structural elements that eliminate thermal bridges and do not compromise the air tightness of the building.

3.   Improved build quality

The third element is that of the build quality: the builder must understand and build to the architects’ details. A small number of builders are starting to build to these exacting standards, but the vast majority, whist not adverse to new methods of working, do not seems to know about or understand the physics behind these ‘new’ build methods.

4.   Better team working

The forth lesson is that all the team involved with the build (the client, architect, consultant and the builder) must work together. The team must understand the concept; know the reasons things are being done in a certain way, and work collectively to achieve the common goal. Not impossible, but not often achieved on a standard UK building job.

Interested in building a Passivhaus, in bringing your home up to Passivhaus standards or using the Passivhaus design methodology? Contact me for a free consultation.

Act now to stay warm and save energy next winter

The summer is here and the last thing any of us are worrying about is keeping our houses warm. Even if you’ve had a new insulated loft conversion done in the last couple of years, chances are the rest of your home could be better insulated.

Two quick insulation wins

I think of my own house and what I could do before next winter. The quickest and cheapest wins are insulating what is known in the business at the ‘opaque elements’ of my home: the exterior walls, the loft and the ground floor, and now, over the summer, is the perfect time to time to get it done.

1.   Insulate the wall cavities

I have considered the pros and cons of cavity wall insulation for many years and have still not done it. Looking at my energy bills over the last year, it’s a no-brainer and I have had it done. I’m not too close to the coast to be classed as “an exposed property”.

The cavity wall insulation was not without its problems. Downs Energy arrived to do the job but on opening up the cavities they found that some of them were full with rubble, well above the DPC level. Filling the cavities without removing the rubble would cause bridging of the damp proof course, so they had to be cleared. Several bags of rubble later and a couple of days labour (which was a cost to me) the cavities were clear and filled.

2.   Insulate the roof

Luckily, my loft conversion is already well insulated, but if you need loft insulation.  I’ve also insulated the ceiling of my flat roof, which has really improved the heat-retention. However, I will check the eaves and storage area in the loft to ensure it is up to the optimum insulation thickness of 270mm.

3.   Seal the floor

The final task I’m going to complete this year is insulating the ground floor . I have sanded and sealed the original timber floor boards. They are beautiful, but cold air rushes in through the gaps and it is often cold, even on a summer day. The problem I have not yet solved is how to insulate under the floor boards without lifting and re-fitting them: I can get underneath the floor but the space is only 400mm (1’ 4”).

Taking your insulation even further

Next year I will look into improving the energy performance of my single-glazed windows, probably by fitting Slimlite double-glazing units or internal secondary glazing. With two large bay windows (five sash windows in each) and four further large sash windows the refurbishment cost will be much more than what I’ll be spending this year!

If you need advice on what you can do to make your home more energy-efficient, contact me for advice or an energy assessment.