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Wednesday, 30 November 2016

Refurbishing old homes with building regs

Part L is different in Wales to England, so be aware of this
Part L of the Building Regulations in Wales (and England) are basically designed around SAP and conventional U value calculations. This is fine for modern conventional cavity walled buildings, but there are issues with older solid walled buildings.

Thankfully the Approved Documents take notice of this fact and they guide you towards some additional advice. Section 12 is entitled: Dwellings of architectural or historical interest. This is broken down into 12.1 Exempt historic and traditional buildings and 12.2 Historic and traditional buildings where special considerations apply.

I think that this is where we get a bit lost, as people don't see their solid walled buildings as being 'historic / traditional'. So many think that this section will not apply to their home. This issue even applies to Building Surveyors and Architects! So wake up Wales (and other countries in the UK), many of us live in older traditionally built homes. Think of all the terraces in SE Wales, stone cottages in mid Wales and  north Wales etc.

So back to the guidance. 12.2 is the big one.

"12.2.1 In addition, special considerations apply to works to the following three classes of non-exempt existing buildings:
a. of architectural and historic interest and are referred to as a material consideration in a local authority’s development plan or local development framework; or
b. of architectural and historic interest and are within national parks, areas of outstanding natural beauty, registered historic parks and gardens, registered battlefields, the curtilages of scheduled ancient monuments, and world heritage sites; or
c. of traditional construction with permeable fabric that both absorbs and readily allows the evaporation of moisture."

So here we are at the bottom of the list 12.2.1 c. Solid walls (random rubble, solid brick etc) are 'traditional construction with permeable fabric'. So they have 'Special Considerations'.

So what are these 'Special Considerations'?

There are several that are linked to the more 'historic' side of the guidance, however there are some key paragraphs that affect your average Welsh Victorian terrace:

"Work to such buildings is required to comply with the energy efficiency requirements as far as is reasonably practicable. In considering what is reasonably practicable, the work should not unacceptably alter or mar the character of the building or increase the risk of long-term deterioration." (p.34)

"Particular issues relating to work to dwellings of historic and architectural interest warrant sympathetic treatment and would benefit from further professional advice. These issues include: enabling the fabric of historic buildings to ‘breathe’ to control moisture and potential long-term deterioration." (p.35)

A link to the Wales' Part 1B Building Regs can be found here

Better than this, the guidance points us towards Historic England guidance on improving energy efficiency in historic / traditional buildings.

Click here to follow link to Historic England advice

This advice goes into a lot of detail about what to do and how. An excellent document. Worth following the link and printing it out for reference.

The missing link for many people is understanding their building. When was it built? Out of what? How has it changed over time? How significant is this? What would be the impacts of change?

There is a standardised and recognised way of achieving this: BS 7913: Guide to the Conservation of Historic Buildings (2013). This British Standard does cost money to buy, but there are a number of key issues that might be important to you and any argument that you might have with building control etc.

Energy improvements to buildings should not harm the physical performance of the fabric.
Some energy efficiency measures can have adverse effects.
Damp walls are up to one third less efficient if damp.
Correct choice of materials is really important.
Correct application of materials is also so.

Much of BS7913 is designed to help those with the more historic end of the spectrum, but it equally applies to an average terrace house (just less so in terms of architectural significance).

Basically you need to be able to understand what your building now is, how it operates, what can be done to improve it safely and considerately. This will no doubt mean that you will not be able to quickly slap a load of modern insulation all expect it to work (ECO? Green Deal?!!!)

So we have to tools and advice to help us get it right for our older buildings (especially important in Wales where we have roughly a third of all stock being 'historic / traditional'), so why aren't we using it?

Hopefully this post will give you some of the information you need to be able to make the right decisions for your home.

Monday, 14 November 2016

Life with an electric car (on test drive)

My test drive car wasn't white and was also sprinkled liberally with advertising
I have just spent 5 days with a Nissan Leaf from Wessex Garages in Cardiff. So thanks for that. My impressions?

The main issue for us was range. Could it do a variety of runs:

Back and forth to UWE in Bristol on one charge (88 miles return)
To Wiltshire to see the family (85 miles one way)
To Merthyr for work (66 miles, but uphill one way!)

Having spent time looking at different makes and models, we decided that the best bet was either the Nissan 30kW Leaf or the new long range Renault Zoe. Renault Retail in Cardiff have been rubbish with any semblance of customer care, so we borrowed the Nissan on a long test drive offer that they had.

The reported range of the Leaf is 155 miles, but in the real world this means around 100-120 miles, dependent on a range of factors. But what are those factors and how would they influence our experience?

The main issues with range are:

Driving style (heaviness of the right foot)
Type of driving (motorway, urban etc)
Location (apart from being on a road, this means whether you are heading up hills or not)

There are other more minor ones like:

Weather considerations (heater on, wipers and lights etc)
Number of passengers

So the first test was to take myself and friend to UWE. The drive there was clear and I managed to trundle along at around 65- 70 mph. Lights on and heater set at 17 degrees. The way back was, as ever, congested and slow especially for the 5 miles around Newport. However the car likes slower driving so this was fine.

On my return home I had 17% battery left (around a further 17 miles), so this test was passed with ease.

The second test was a bit more tricky. To Pewsey in Wiltshire with the whole family (4 in total) and a boot full of clothes, wellies, food for chickens, (warning triangle and first aid kit - at the wife's insistence) and three very large helium balloons for my niece's 21st birthday - these might have helped! 

I had checked the height above sea level before the journey (this is the level of detail required when one has a doubting Thomas aboard) and it was over 200m higher than the trip to Merthyr. So if it could make it to Wilts on one charge it could certainly make it to the borders to the Brecon Beacons National Park and back!

The confidence in the journey was bolstered after the trip to Bristol and its associated levels of reserves upon return. My foot was therefore a little heavy and I admit that there were times (quite by accident) that I found that we were travelling at faster than 70mph. However, what with all the hills in the way by the time we got to Chippenham (and our last chance to have a rapid top-up) we were down to 30 miles projected range. At that point I was trying to remember how far we had to go (was it 20 or 30 miles???!!!) I kept up the optimism and assured everyone that everything was fine and that we would make it.

As the miles clocked by, so did the battery storage %. By the time we were heading into the Vale of Pewsey the warning lights were on and there was a certain air of concern. However, we pulled up into the driveway with 11 miles 'still in the tank'. So we had made it. The extra height above sea level combined with some less than economical driving had caused a little minor panic, but we were there.

On the way home, we were of course heading downhill back to Cardiff, plus we were being more aware of our driving techniques, so we actually arrived back in a slightly heavier car (due to the addition of some lovely garden veg and the loss of three large helium balloons) with 21% battery life remaining.

No need to do the Merthyr run as we can now be confident in the Leaf's ability to do 99% of all the journeys that we need it for.

Charging the car would cost us around £3.50 from zero to full for around 100 miles, so a considerable saving. Also with the PV panels on the roof we may manage to get some very low cost charges in the lighter months during the day. Time will tell.

It is a completely different set of factors to think about when driving an electric car. Checking distances prior to leaving, identifying charge points etc. but nothing too difficult or out of the ordinary. The car itself was comfy, easy to drive (although odd not having gears per se), quiet and able to give a warm glow inside the driver!

My brother and mother were also very impressed as I took them out for a ride as well. Mother was impressed with the road holding and quietness, whilst my brother, of course, had to test for its renowned acceleration! 

I thought that it was worth putting this on a Eco Home blog as there are implications for housing. Where to park the car to facilitate charging, where to put the charging point, how to store some renewable energy effectively for later use, how to cut carbon emissions if there are limitation on what you can do to the fabric of the house etc. So if you are in the market for another car, I would suggest that you have a think about what you need it for and whether an electric one would suffice.

Also on another note, if you are an Ecotricity Dual Fuel customer (which we are), then you also get £40 back from them just by having an electric car, plus you get free charges from their network of charging points (there are some limitations to this re number of charges per week, but all the same!).