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Easy-fit letter box draught excluder

Tag: sash windows

Glazing: A to Z of draughtproofing

Glazing

Glazing makes a critical difference to the success of any energy efficiency building upgrade. A central plank of passivhaus or EnerPHit projects, paying close attention to it in any works will pay dividends. Glazing can be responsible for making a building comfortable and for making it draughty. Here’s how to make the most of it and avoid the pitfalls.

glazingWe looked at passive cooling in episode 7 of the podcast. This is the science of using the environment together with good design to keep a buiding a comfortable temperature. Glazing can make a big contribution here. 

Use a building’s orientation to maximise solar gain (ie have the sun shining through big windows for as much of the day as possible). Ensure the house is effectively draughtproofed to keep that warmed air in the house and at temperature. Use shutters or blinds to keep the sun out if you’re getting too warm.

In cooler weather shutters and particularly blinds and thick curtains can help to insulate the area around a window. However this is only useful if a window is not letting through gales of cold air.

Blocking draughts

The best way to avoid draughts in modern houses is to block up cracks and gaps. It’s important though to distinguish between windows that just aren’t very insulation, ie a single pane, and windows that have actual gaps around them. If you can afford it, have poorly-insulating windows replaced with the highest-performing alternative you can run to.

Before you start work, understand how your windows contribute to overall airflow in the room. A historic building will have different considerations from a recent new build. If you have a new build don’t rely on the energy performance information you’ve been given. There are numerous instances of new builds falling short of the advertised energy performance due to poor construction.

Plug gaps around non-opening windows with silicone sealant. Use a sealing tape or strip to keep openers draught-free, double checking the opening action isn’t impeded. 

glazing

Historic buildings

Obtain expert advice if you live in a historic building. Simply plugging gaps around windows in older buildings can cause problems with damp building up. Understand the airflow and how your house and each room behaves, particularly in a house with multiple building phases over a few hundred years. Consider how different areas of the house are heated. Look at their solar gain and loss.

Windows have a role to play beyond letting in a cool breeze or keeping out the elements.

Retrofit for energy efficiency success

What makes a successful energy efficiency retrofit?

Badly designed energy efficiency retrofit can cause more problems than it solves

Badly designed energy efficiency retrofit can cause more problems than it solves

Short-term thinking: a retrofit disaster

I read an article on the Sustainable Homes website today that brought to mind a conversation with an ex-colleague, the property manager at a historic house in the south east of England. Her point was that ever since the sash windows had been sealed in their offices, the windows ran with damp and surely this couldn’t be a good thing. She’s absolutely right and the cause is as described in the article on the blog:

The tendency…to focus on the immediate and short term, with the consequent potential for a poorly designed and risk-controlled project, has long been a concern.

ECO funding

This article was looking at the implementation of ECO and specifically its focus on the short-term fix and goes on to look at organisations that have preferred to run projects without this type of funding, eg Viridian Housing, in order to retain more control.The blog post is a response to an article from Inside Housing (you need to regsiter to read articles) questioning whether energy efficiency work was in fact causing rather than solving problems for social housing tenants, but as the SH blog comments:

poor design, planning, procurement and delivery will create significant problems, and that’s the case for any work irrespective of why you wish to carry it out.

Active management

It’s vital particularly in this context to distinguish cause from effect. The author of the blog post, Tony Jarman of Your Homes Newcastle, points out the dangers of box-ticking to qualify for funding in an areas that “has to be actively managed”. He outlines the areas of skill and expertise that are required and the planning and monitoring pre- and post-retrofit that must be carried out. Otherwise, as he says, energy efficiency could become “the villain of the piece” and that would serve no-one.

Going back to that conversation I had, it’s all about “active management” of ventilation. Draughty sashes aren’t comfortable, but properly maintained and used as originally intended sash windows provide excellent draught-free ventilation. Sealing them up and bringing ventilation to an abrupt stop allows damp to build up. Apart from being uncomfortable to work in, damp is very dangerous for any building and will lead to a host of problems. Draughtproofing yes, lack of controlled ventilation no.

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