Retrofit for the Future
The Retrofit for the Future ideas competition which ran from May to mid-November ask Manx residents with architectural backgrounds, studying architecture, building retrofitting expertise or those with a passion for green construction to submit designs which could significantly improve the energy performance of an existing Manx home to make it a future-ready building.
Judges were particularly interested in ideas which tackle Manx stone cottages, Victorian semi or terrace housing and 1970s-style bungalow homes. Current generic solutions including roof, floor and external / internal wall insulation may not be suitable for these properties as it may cause problems such as condensation, change in external character of the buildings, reduction in size of rooms and loss of internal features such as cornicing. Ideas generated from the competition could lead to suitable options to improve the energy efficiency in these properties which will reduce emissions and help tackle climate change.
At the awards ceremony on Monday 9 December Minister for Environment, Food and Agriculture, Geoffrey Boot MHK presented Deb Cripps with the main prize of £5,000 for her submission which included ideas and techniques for increasing the energy efficiency of a 1970s bungalow, a style of residential property which can be found in large numbers across the Island.
Bullet Points on Key Topics Re Design Ideas Entry,
Entry 1 - Craig Mullinor
- Used a 1970’s dormer Bungalow as example building
- Good explanation and communication of background to value of clear understanding of building layout/dimensions and component parts of where a building uses energy and options to measure and improve this.
- Good use of accurate floor plan data to demonstrate where energy improvement options could be provided, and when these options might be appropriate. Useful indications of weak points in existing building and where improvements would be appropriate to resolve issues.
- Good understanding of prevailing means of assessing Energy Performance of a Building (EPC) and SAP and how these would be assessed.
- Made useful suggestion that making use of something equivalent to UK’s Energy Performance Certificates (EPC) would be helpful for homes, and would be of use to prospective buyers and sellers of homes to communicate their relative performance.
Entry 3 - John McCarrick
- Survey each existing property
- Undertake air-test to assess air leakage through the current materials and wall junctions
Upgrade Thermal Elements:
- Where practical, remove existing render and replace with a Parextherm Acrylic Render System (or similar approved) to improve the external air leakage. Brick work or stone work could also be rendered depending on the Governments’ preferred finish
- Use air-tightness tape on junctions and around windows and doors (erecting porches or draught lobbies where property’s do not have a wind break to their front door)
- Use plaster finishes onto walls to help reduce air-gaps and where practical install a layer of insulated plasterboard (with breather membrane) onto all external walls with moisture resistant board to bathrooms, kitchens and utility rooms
- Remove existing floor screed on solid floors and where practical install insulation and perimeter insulation upstands prior to re-pouring screed. This will improve insulation on the Ground Floor, however an insulated floating floor maybe an alternative option. Timber floors can easily be upgraded with new and more thermally advanced insulation between and over floor joists
- Roofs can be thermally upgraded with improved insulation
- Where practical and without severely decreasing the floor area, housing insulation should be upgraded to ‘Passive-haus’ standard levels in order to reduce the requirement for heating appliances
- Pitched roofs should maximise the use of photovoltaic cells and individual wind turbines where noise isn’t an issue
- Use of localised Septic-tanks and soakaways to reduce strain on the main sewage and water system
- Installation of heat recovery systems would be more practical where ‘Passive-Haus’ standards can’t be achieved.
Entry 4 - Paul Lenartowicz
- Proposal used a 1970’s bungalow as template.
- Areas of heat loss identified and options to resolve these issues proposed.
- Rigid insulation panels fitted to external walls, supplemented by internal wall insulation.
- The result of all the works for householder expected to reduce fuel bills by half
- Triple glazing meaning windows used to reduce heat loss from windows
- Mechanical Ventilation Heat Recovery used to recover heat from the whole house ventilation
Entry 6 - Tilo Gutzold
- Proposal featured applicants own home and their improvement options undertaken to their property.
- Example property was a 1970’s bungalow, of which there are several thousand in the Isle of Man, so a common housetype.
- Applicant showed good data of previous energy usage figures and the changed since the solar PV panels were fitted, alongside the Air Source Heat Pump and power storage system (Tesla Powerwall)
- Costs of the improvement options eloquently explained, as well as the financial payback for the exercise giving a business case for the chosen decisions made.
- Photographs included in the entry were informative as to how the technologies look, which makes it more accessible as an understandable technology, not a text book or internet only example.
- PV panels, powerwall and Air Source Heat Pump would be relevant for many further properties.
- Total costs of works clearly articulated, and before and after running costs of home energy use - £31,500, savings PA £1500, with combination of solar PV, Tesla power wall energy storage and Air Source Heat Pump. Estimating payback within 15 years.
Entry 8 - Chris Hardisty
Applicant is qualified bricklayer experienced in many types of construction, and now retraining as a construction industry professional and currently a part-time student.
- Example provided was 1970’s bungalow
- Replace external elevation finish with external wall insulation – re finish in brick slips or render or combination
- Removal of outer leaf to parge coat for airtightness insulate & rebuild
- Proposed utilisation for construction sector of trade bodies like AECB (Association of Environmentally Conscious Builders) for up-skilling construction sector
- Solar PVs
- Air source heat pump
- Centralised Mechanical ventilation heat recovery (MVHR) system
Entry 12 - Mark Haith
Entry describes works undertaken to improve Edwardian (110 year old) property, sympathetic to its heritage using suitable materials, eg
- lime mortar & plaster,
- sheeps wool insulation and
- cork board in walls.
- heating needs now provided by air source heat pump, replacing an outdated coal heating system
- extensive draft proofing works (eg draft proofing doors, capping of chimneys etc),
- Whole House Heat recovery and ventilation system installed (REGA system), which recirculates air from top to bottom of the property, and removes humidity from the air.
Suggests the creation of an online forum for Manx self-builders looking to restore stone buildings and retrofit insulation with eco-materials would be very helpful
Entry 13 - Richard Crane
Victorian (1896) mid terraced two story house in a conservation area, and its renovation by owner-occupier.
- Owner has shared their experience with neighbours and builders with the aim of sharing good practice and lessons learnt.
- Entry shows great amount of research during process, and thorough understanding of property and what might be suitable to improve it.
- A notable learning experience has been that the original lime mortar has failed, and any re-pointing since has been with sand/cement. The result has been predictably poor sealing of the outer brick leaf and the ingress of damp.
- re-pointed the front elevation with conservation matched lime mortar
- following the drying out of the walls, further insulation value was added on internal elevation by use of Gyproc "Sound Coat Plus, and then thermal backed plasterboard
- future stages of work planned include attic insulation, addressing other areas of air ingress and ultimately some air treatment to ensure both movement and quality of the air in the home.
Entry 16 - Trevor Clark
Very comprehensive entry (63 pages in length) featuring extensive understanding of the range of different house types of the Isle of Man, their respective differences and how to address energy efficiency in them.
- Stone Build Manx Cottage – Solid Stone (or Brick/Block) walls
- A Victorian Semi-Detached House – Cavity wall brick construction
- Terraced House – Brick cavity construction, with brick cavity party wall
- 1970’s Bungalow – this type was further described for a Full Energy Retrofit.
- Usefully describes 12 Steps to Net Zero and Energy Comfort, relevant to any property.
- 1. Weather Tight – keep the water out
- 2. Orientation – Building, Structural Openings and Energy Collectors
- 3. Simple Design – Keep It Simple
- 4. Thermal Mass
- 5. Airtight Building Envelope
- 6. Balanced Insulation
- 7. Ventilate Right
- 8. Efficient Balanced Energy Input
- 9. Efficient Domestic Hot Water Generation
- 10. Efficient Domestic Appliances
- 11. Efficient Lighting
- 12. Alternative Renewable Energy Generation & Balanced Storage
- Costs have also been estimated to upgrade this notional example 1970’s bungalow with an internal floor area of 96.15m² retrofitting to near Net Zero the cost would be in the region of £82k, including the renewable energy components
- A medium level of retrofit to this notional property retrofitting to near Net Zero the cost would be in the region of £50k including the renewable energy components