Passivhaus Consultant and Designer.  Very Low Energy Buildings.  Domestic and non-domestic.  New build and refurbishment. 

07502 425158

Bristol, UK



Grade II* Listed Building Refurbishment

We have recently been appointed to advise on servcies and roof insulation for this Grade II* Listed house.

The heritage value of the building dictates most of the works with restoration as the main driver.  The focus for energy efficiency is on insulating the roof and providing energy efficient heating and hot water.

We are advising on design and procurement of a 50kW water source heat pump with oil backup for heating and hot water.  



The geometry of the roof, combined with the historic structure makes insulating the roof effectively without risking damage highly challenging.  





Three rules to make Passivhaus much easier

My July blog for the Green Register explains how to make it much easier (and cheaper) to build a Passivhaus.  These rules aim to guide designers and clients on key features from the outset.  If you don't take note of these riules you probably won't end up with a Passivhaus and your house will be much less energy efficient than you probably hoped.



New 26 Unit Passivhaus Development in Bristol

Piers has been appointed as Passivhaus Consultant on a scheme to build 26 Passivhaus dwellings on the site of the former bingo hall in North Street, Bristol.  The project team for the development, known as Picture House Court is as follows:

Developer - North Street Investments

Architect - Origin 3 Studio

Passivhaus Consultant - Piers Sadler Consulting

Passivhaus Certifier - BRE Certification

Structural Engineer - Hydrock

M&E Engineer - Hydrock

Project Manager - Aecom

Main Contractor - Speller Metcalfe


Construction work started on site in 2013, but was stopped whilst a new team was appointed for the project. Work is about to start on site agin, and whilst Passivhaus work was done before the original start on site with Origin 3 working with BRE, there is still a lot to be done to confirm the suitability of the designs and performance through PHPP.  

These are relatively complex buildings, so there is a lot of work going into thermal bridge free and airtight design.  Airtightness is clearly going to be the key challenge.  To get up to speed with the project quickly and aid the smooth running of the Passivhaus consultancy Piers was co-located with Origin 3 Studio for about 6 weeks at the start of the work.






Room in Roof Insulation - a risky business

The complex geometry and construction of room-in-roof settings, especially in older houses, makes them very difficult to insulate with appropriate vapour control and without risking interstitial condensation and potential building damage.  


Similar issues in relation to solid wall insulation are well documented and solutions presented in the excellent new 'A Bristolian's guide to Solid Wall Insulation'.

Piers has been grappling with this on a number of projects and produced a blog post for the Green Register describing the problem and recommending an approach that addresses most of the issues.


Passivhaus Bristol Conference a great success

Bristol Green Capital Place Group, put on a Passivhaus Conference in Bristol on 17 November 2015 entitled:

" How can we build greener and better buildings?  The case for Passivhaus development"

Piers Sadler led the organisation of the event supported by Place Group members and gave a presentation entitled: What is Passivhaus? which is available for download

A packed audience at Arup's Bristol office heard high profile speakers from around the country explaining why their organisations have adopted the Passivhaus Standard and the difficulties, solutions and benefits that they had encountered.  There were great presentations on Passivhaus schools and social housing and on how Exeter and Norwich City Council's have adopted and are encouraging Passivhaus development in their areas.  We were particularly privileged to hear about Exeter City Council's ground breaking leisure centre and swimming pool project, the first of its kind outside Germany.  This building will save about £200,000/yr on energy costs which will pay off the additional costs of Passivhaus in about 12 years.  We also heard about Bristol's much more modest plans which do involve Passivhaus, but we are hoping that events like this will encourage Bristol City Council to up its game when it comes to low energy, healthy housing which works as it's supposed to ie Passivhaus.