Can I fit a heat pump? What do I need to know?

At the start of 2022 we finally got rid of the gas supply to our home, and retrofitted an air source heat pump. With the high proportion of renewables in grid electricity now, this has led to an absolutely huge cut in our household carbon emissions, and we are delighted with how it has performed so far.

picture of a heat pump
Our Mitsubishi Ecodan

While we were planning this, I wanted to know more about what the process entailed and what we would need to think about – so I decided to write an article about it. I learned so much that I ended up writing a two-parter. Continue reading “Can I fit a heat pump? What do I need to know?”

What is thermal bypass, and why does it matter?

I am greatly indebted to the meticulous working and thinking of architect Mark Siddall (LEAP architecture) here. He’s been talking about thermal bypass for a while, so I asked him to walk me through the basics.

What the term ‘thermal bypass’ means is cold air (usually cold – though of course in summer it could be too hot instead) washing through building fabric, and undermining the thermal performance.

This means that in winter, cold air may be moving around in the walls and roof and taking heat from indoors, even if it doesn’t actually break through any air barriers. A classic example is when insulation is loosely bunged into a cavity, and warm air behind the inner leaf is drawn away and replaced with cold, when it should be held snug against the fabric.

My interview with Mark and some explanations and examples were written up for SIGA, and you can read them here.

A leaky fabric is no substitute for ventilation

In some corners of the construction community there is still a lurking belief that a leaky fabric is needed in order to ensure good indoor air quality.

But gaps and cracks are random, and the air flow through them, even more so. Believing a leaky fabric will contribute usefully to indoor air quality is an act of blind faith. Continue reading “A leaky fabric is no substitute for ventilation”

Cotswold stone warehouse becomes Enerphit hostel

The Barrel Store; once a warehouse, now a super-low-energy hostel: photo courtesy New Brewery Arts / The Barrel Store. Photography by Max McClure

This 150-odd-year old historic stone warehouse in the centre of Cirencester has been very carefully converted to create a youth hostel, providing much-needed budget accommodation in this pretty Cotswold town.

An Enerphit retrofit lifts the comfort way above the usual draughty-old-house-that-was-impossible-for-the-owners-to-heat that may be many people’s experience of UK youth hostels. Continue reading “Cotswold stone warehouse becomes Enerphit hostel”

Downsizers’ Passivhaus marries natural materials with high renewable tech

 

This light and airy Passivhaus was built by a retired couple who wanted to downsize from their awkward older home, to one that would be eco-friendly, comfortable, and work well whatever their future needs.

The successful result is an attractive, warm, modern-looking house. The structure is timber frame with wood-based insulation; the roof meanwhile is basically all PVs, and a heat pump and battery complete the comprehensive renewable set-up, minimising the need to import – and pay for – any grid energy.

Read the article I wrote for  Passive House Plus magazine here.

Straw-build Herefordshire Passivhaus – one of my favourite case studies!

black coloured timber clad wall with shaded window and pot plants in front
Detail of the charred cedar facade showing lowered sunshade for summer comfort. Photo: Juraj Mikurcik

Juraj Mikurcik’s beautiful little self-build Passivhaus is a house that I can totally imagine living in myself, and absolutely loving. Continue reading “Straw-build Herefordshire Passivhaus – one of my favourite case studies!”

Preston Retrofit Disaster

An external insulation contract in Preston, run under a government energy saving scheme five years ago went horribly wrong. Up to 390 homes were affected with water penetration, mould and damp.

Four years on the problems, some of them severe, have only been rectified for some of the affected households. Occupants, many elderly and on low incomes, have in some cases reportedly been forced to pay for repairs themselves. Continue reading “Preston Retrofit Disaster”

Grenfell Fire

Like everyone, I was horrified by the events of June 14, 2017. I felt additionally anguished because I had written so often about poor standards and corner cutting in construction, without ever imagining the consequences would be so devastating. But we knew, didn’t we, that risks were – and still are – being taken.

I wrote a long piece for Passive House Plus looking at the background to the catastrophe: in particular, examining how such highly combustible cladding might have come to be used. That article is here: Grenfell Tower – how did it happen?

I also wrote a follow-up piece on the concerns of many fire experts that too much information about product testing was being kept secret due to commercial confidentiality – and that that the information that was kept secret, might have led to better design choices had it been available. The story also contained calls for combustible materials to be banned entirely from tall buildings as they are in several other countries. A further news item reported Dame Judith’s shock at the lack of accountability and the obvious opportunities for corner-cutting in mainstream construction

And I contributed to some of the very thorough coverage of the subject in Inside Housing magazine – you can read the relevant articles here and here (you may need to create an account to read these if you are not an IH subscriber).

UPDATE: Now the Public Inquiry has opened, a great deal more information is becoming available. Sessions and background evidence submissions are being posted in the inquiry website here. Dr Lane’s is one that has been reported as containing a huge amount of important detail. If anyone finds anything they think needs wider coverage, do get in touch: mail “at” katedeselincourt.co.uk.