Case Studies

CASE STUDIES – Low Carbon – Rectory

The new building located within an area of “Townscape Character” takes its design influences from several other buildings in the neighbouring area. Although taking into consideration design features such as easy access,future lift,energy efficiency etc we needed to ensure that this new home was robust, durable and adaptable to any future change.

Using tried and tested sustainable materials such as clay brick,concrete block, plaster,natural slate etc, a modified and more precise traditional building approach was taken using a skilled workforce leading to the successful completion of this highly energy efficient and comfortable home.

Although this building approach was the first of its kind I have undertaken ( if not indeed undertaken in UK/ Ireland) and numerous strict controls were set from the beginning of the project I was delighted to find that most all the trades involved in the project took a very keen interest in the modified approach and responded with great enthusiasm and a willingness to “do the job to this higher standard”.At the start of the project the skilled labour force prior to carrying out each trade was shown examples of modifications/preciseness needed and asked to consider the challenge ahead. A “Sample Walling Panel” was constructed on-site prior to super-structure commencement to “eliminate” any doubts or apprehension’s. Although questioning many modified conventional construction approaches they quickly adapted and applied their individual skills to a higher level of preciseness which has unfortunately been suppressed by poorer accepted standards of recent times.

Convention has taught me that numerous types of materials,construction types and skills have developed over the years and survived because they are robust,of quality,are affordable and flexible for the designer and most importantly THEY WORK.

Also they can be easily worked with at a later date of alteration/modification and this was the driving force behind my approach to this design which after all was a building of symbolic importance with “Whole-Life” expectations.

The building designed with durability,flexibility,longevity,robustness,high energy efficiency etc in mind has to withstand the many uses that will be imposed on it for years to come.

This build represents a high quality of construction that incorporates cost effective,locally and responsibly sourced solutions to the higher levels of the “Code for Sustainable Homes” whilst also addressing the needs of the end-user for long-term,durable,flexible and low maintenance requirements.

Although traditional in appearance and build-type this Rectory conceals a very high level of skill,a highly insulated fabric,high level of air-control and renewable energy installation.

The Contractor on the job has publicly stated;

“ Even though I have built many homes over 20 years in the construction industry, this project presented me with a great challenge of constructing a low carbon dwelling using only traditional materials such as concrete and masonry, whilst also applying skills to a modified and more precise level”.

Using the benefits of heavy-weight construction including “Thermal Mass” ,incorporating Internal Yard, zoning of Heated and Unheated Areas and centralised “Plant Room” to create shorter circuits and maximising efficiency of all services allowed the low temperature Air –to- Water Heat Pump/underfloor renewable heating installation to satisfy the busy occupants requirements of comfort with ease and convenience.

Completed in spring of 2012 this project is (to the best of my knowledge) one of only 12 homes in N.Ireland to achieve a Low/Zero Carbon Rating attracting in this instance 2 year rates relief.

Designed to achieve the PHI target of 7kWh/m2/year for space heating alone.

Case Study Zero Carbon – Private House

Introduction

Whilst others have adapted timber frame or other proprietary building systems to achieve Zero Carbon Status this build achieves this utilising only traditional building skills and locally sourced materials that will endure and remain sustainable. Simplicity is the key to our approach in this build proving that little really has to change other than we “reinstate” good building qualities & practices to precise levels.
Utilising the experiences gained from the Low Carbon Rectory Project using heavy-weight construction comprising concrete block cavity walls,render & plaster ,high levels of insulation/air-tightness and maximising thermal solar gain/thermal mass put-together  in a precise manner has led to this large property achieving net – zero carbon rating – the FIRST of its kind in Northern Ireland and possibly the first or one of very few in all of Ireland and UK.
With global warming upon us , it has become more important to consider using materials and methods of construction that are sustainable.It is also apparent that in the art of constructing a building there is an ever increasing need for quality,emphasised by increasing requirement levels for low cost ,high energy efficiency ratings.
In this build approach several aspects have been questioned:

• “Why should a modern constructed zero carbon home be so different from convention?”
• “Why should reliable tried and tested solutions to materials and construction skills gained over many years be simply discarded or no longer relevant?”

The answer is simple “NO REASON”

Backgound

What we have achieved in this project is a conventional, affordable and sustainable solution which is derived from tried and tested building traditions.
Coupled with an understanding of compatible renewable energies  and on- going site experiences this net – zero carbon home is not compromised in design and is robust,durable and built using traditional masonry products that are available and locally sourced.
Developing this modified conventional “fabric-first” approach and optimising the insulation performance of the building envelope, high level of air-tightness, and economic and energy efficient centralisation of services results in     “ affordable and comfortable living” with a practical core function of robustness and every-day ease of use.

My clients intention from the start in designing this 371m2 ,2-storey four bedroom house on their 18acre holding was to achieve an ‘A’ Building Energy Rating/Zero Carbon Emmissions home using conventional masonry materials/traditional construction types that are durable and adaptable at later stages or during the build.
Having already designed a “Low Carbon Rectory” using this approach, it was apparent to me that with practical and focused thinking it wasn’t going to take too much input to achieve this standard.
My client also with building experience wanted an approach which would not only gain significant cost savings in the long term with little or no energy bills but would have significant “whole-life” durability with minimal maintenance.
I was determined however not to let the energy requirements over- restrict the design and client aspirations as this would have been counter productive.

Construction Approach

The new house combines four main factors : – It is built from heavyweight construction, has high levels of insulated external fabric/ airtightness and uses Thermal Mass.
Using medium/high density concrete block walls externally/internally with modified wide insulated cavity,solid concrete block walls internally together with concrete insitu ground floor – insulated at two levels,concrete suspended first floor and concrete suspended insulated ceiling – all creating high levels of insulated fabric with good sound insulation qualities.This arrangement coupled with two internally placed concrete block chimney’s capitalised on “thermal mass” absorbing heat during the day and releasing at night.
Areas of maximum glazing are located on southern aspects whilst care has been taken to minimise glazing to the north with utility space uses such as Bathrooms etc placed on these facades.
The sunroom ( with large expanse of glazing ) and modest entrance Vestibule ( where south-westernly winds will prevail)  have both been designed to incorporate inner separation walls/apertures that are to External Fabric Energy Performance Standards this to protect the energy performance of the inner rooms in times of maximum use,high winds and cold temperatures.

Services

Placed within the buildings central core and positioned in a vertical stack formation, are dedicated Plant Rooms on Ground,First and Attic levels accommodating ALL mechanical and electrical installations.All services entering through the highly insulated external envelope ( “cold-to-warm areas” ) of the building do so at only a few positions in this area so allowing a very high level of airtightness control. Heat recovery ventilation takes advantage of heat producing internal appliances and warmer roofspace environment. A 1500 litre Thermal Store warmed by log stove and hybrid thermodynamic solar panel system and array of Solar Photovoltaic panels supplies heating and electricity that ensures that the house has zero running costs but also contributes a modest profit to the household.

Completed in late December 2012 this building is a first in Ireland to achieve Zero Carbon Rating using only conventional cavity wall construction approach but much more importantly paves the way for the Zero Carbon Affordable and Comfortable Living solution in the UK and Ireland.
Unfortunately this special house did not attract the Governments 5 year free rates due to time-lines which closed the scheme earlier this year.
Pity really as efforts like this should be rewarded!

Designed to achieve the PHI target of 7kWh/m2/year for space heating alone.