Why Retrofit?

It is widely accepted that deep retrofitting our existing housing stock and building Passive Standard new builds is critical if we are to not only achieve Net Zero, but a reduction in energy consumption and reduce bills.  Around 18% of our annual national CO2e emissions come from existing homes , and these will still be standing in 2050. 80% of 2050’s homes have already been built.

It is essential to retrofit homes correctly so work is only done once.  But if we retrofit homes well, we can enjoy many environmental, social and economic benefits.

We undertake whole house deep retrofit projects around Guildford, Surrey and the South East.

What is Deep Retrofit?

A Deep Retrofit takes a whole house approach, upgrading the building fabric including improving insulation, air tightness & ventilation. It incorporates energy efficiency measures and the installation of low carbon heating. The targets for energy consumption should be 60-80% for the average UK home although this may vary depending on building type.

There is a real potential risk of poor air quality and damaging moisture issues when a piece meal approach is taken to retrofit. It is perfectly acceptable to spread aspects of a deep retrofit over a period of time, but it is essential to understand the impact of changes made to a building at each stage. We can create a plan for your retrofit that minimises risk to the building and and maximises reductions in energy consumption and CO2 production.

What is the first step to Retrofit my home?

The first step is to meet up and have a conversation about what your aspirations are for your home, what any existing issues are and what sort of energy expenses you currently have. If you are planning on major refurbishment and home improvements or extension works, then that is a perfect time to get started on retrofit.

It is essential to fully understand the building, its current condition, and potential risks prior to starting retrofit works.

We will assess the property from top to bottom and evaluate its current condition and its suitability for various retrofit improvements. This is mainly a visual inspection and not a structural survey. It will sometimes include the use of damp meters and thermal imaging cameras where appropriate to highlight areas of damp timbers, missing insulation, thermal bridges and points of air ingress. Damp and moisture build up in homes is common but more often than not, is due to simple issues such as blocked or leaking rainwater goods, external ground levels too high and condensation from daily life with lack of ventilation. We will aim to identify and give solutions to rectify the source of these problems. We will identify the construction of the existing building along with any inappropriate works and use of materials that may have been done in the past that could cause current or future problems.

A full report will be written outlining urgent maintenance items that should be addressed before retrofit work starts, identify easy wins for short term energy reduction and list all measures that will form the retrofit improvement and sequencing including insulation, heating, ventilation strategy and moisture management.

If appropriate we can arrange for a blower door test to be undertaken at the same time as our assessment to highlight areas of air infiltration (draughts) and to also give an understanding of just how leaky your home currently is. A door blower test works really well in conjunction with a thermal imaging survey, as this gives a visual indication of location of air leaks.

Retrofit of older homes

We aim to take an approach to retrofit that is sympathetic to the age and construction type of your home. An important part of this is understanding how your home is built and its suitability for different kinds of works. We have a good understanding of what detrimental impact some modern methods of insulating and ‘improvements’ can have on older homes and will advise accordingly.

Further stages

We can work with you, your architect if you have one, and your builder to ensure that works are designed, detailed and constructed to achieve robust levels of insulation and air tightness using Passive House principals. We can undertake on site training and quality control to ensure the performance of your home meets the designed standards.

If required we can produce a PHPP (Passive House Planning Package) model to help make design decisions and fully understand the requirements and future energy consumption of your home. This is a requirement if you want certification for an AECB, LETI or Passive House standard.

Why follow a building standard?

Building an ‘eco’ or ‘low energy’ home to no particular specification or guidelines can bring with it a host of problems such as under performance, overheating or air quality issues that would undoubtedly leave home owners unhappy with the results. It is far better to design and build to a specific criteria and this is where  building standards such as the AECB Retrofit Standard or LETI Climate Emergency Design Guide can be used as a measure of performance and a target for home owners, architects and builders to work towards.

LETI Retrofit Standard

The LETI retrofit standard uses Passive house principals and modelling and has its own target levels suited to UK housing stock.

On smaller projects or where finances may not be available it is possible to follow the LETI retrofit fabric and systems targets that do not require the expense of a PHPP model.
The flow chart below gives a really useful guide to help clients make a choice about what their targets for their home may be. Click images to enlarge.
LETI Climate Emergency Retrofit Guide