It may not be glamourous, but at greentomatoenergy we believe in applying the laws of physics to low energy building. In order to mitigate against the risks of low energy building (primarily performance, cost and fabric), our team of engineers will apply real science to your project. This will give you the confidence that the work you are doing will deliver lasting results.
We are an independent consultancy that will propose the most appropriate solutions, helping you to avoid the minefield of technology-specific salespeople.
Consultancy Services for Home Owners
Our energy surveys are carried out by engineers with experience and training in low energy refurbishments. The survey consists of both a site survey and an analysis of your energy profile.
Your greentomatoenergy Energy Survey is tailor made to suit your requirements and can provide advice on future developments such as loft conversions and extensions. (In fact this ideal time to implement low energy measures)
- the building fabric elements that make up the thermal envelope
- heat loss through ventilation
- the energy efficiency of your heating system
- your energy bill’s, in order to benchmark your property’s energy demand against various industry standards
- Your property’s suitability for renewable energy generation.
Recommendations are then made to reduce the heating demand and to increase the comfort of your property.
Our Low Energy Design service is available for both new builds and refurbishments. With greentomatoenergy’s advice most property’s can be designed up to PassivHaus if desired.
Low Energy Design is made up of three parts:
1) Design Brief
The design proposal is reviewed and improvements are suggested greentomatoenergy then models the property using the energy modelling software PHPP. A baseline model of the property, as existing or to building regulations is created; this is then amended to an agreed energy target. The model and its outputs are reviewed and discussed with the client and the architect and adjustments are made if necessary.
The design brief provides you with the following outputs:
- Building fabric build up recommendations, looking at the thermal envelope as a whole
- The estimated reduction in energy demand due to the proposed measures
- Options for different energy targets
- Confirmation that the project can meet certain benchmarks eg PassivHaus or EnerPHit
2) Detailed design
greentomatoenergy works to make sure the design is as energy efficient as possible, and continuously calculates the changes on PHPP. Other services at the detail design stage include;
- Minimisation of thermal bridges
- Fabric specifications on all floors, walls, roofs, windows and doors
- Increasing airtightness by eliminating ‘holes’ in the fabric with an airtightness layer
- Specification of heating and ventilation systems
- Advise on lighting and low energy appliances
- Renewable energy specification
If required greentomatoenergy can work with builders to make sure that the plans are correctly implemented. This can include;
- Airtightness testing at various stages in the construction
- Advise on creating the continuous airtight and thermal layer
- Installing and commissioning ventilation and renewable energy systems
greentomatoenergy can also monitor how the building performs in use after the development has been completed.
Commercial Consultancy Services
Energy audits are necessary to improve energy efficiency in an existing building. An energy audit consists of collecting and analysing energy consumption by fuel type and end use to understand how the building is performing and where improvements can be made. The following steps are implemented to enable us to make recommendations:
- Gather electricity and fossil-fuel consumption records (bills/meter readings prior to site visit)
- Comparison of energy consumption to current industry benchmarks
- Walkthrough survey (to survey in-use systems)
- Interview with occupants and maintenance team
- Breakdown of energy consumption by end use (where possible) (using CIBSE TM22)
- Recommendation of energy efficiency measures
Assessment of applicable financial incentives and financing schemes
A bespoke low energy strategy can be created for a specific project. These services include:
- Design review of current proposals to see which low energy interventions are feasible
- Thermal model of the building with PHPP (Passivhaus Planning Package) to be used as a design tool to assess the impact of each energy efficiency measure
- “Low Energy” design brief (including fabric, airtightness, ventilation, heating and renewable systems strategies)
- Passivhaus compliance check and feasibility analysis – where requested
- Renewable energy feasibility studies (including paybacks and grant funding)
- Tender analysis and support
- Provision of information required for planning process/Energy statement
Many projects arrive at a point where modelling is required to give exact numbers or validate a proposal. These services include:
- Thermal bridging detailing and modelling (using THERM)
- Hygrothermal simulation and condensation risk analysis (using WUFI)
- Overheating risk analysis
- Daylighting analysis
- Dynamic thermal simulation
- Heat load calculations
Low energy building is not without risks and often the main purpose of our design work is to mitigate those risks and to ensure that the building will perform well. This is achieved by a great care and attention to detail. These services include:
- Passivhaus and EnerPHit compliant detailing
- Insulation specification and opaque fabric build-ups
- Glazing specification and installation details
- Airtightness design advice and detailing
- Thermal bridging design advice and detailing
- Space heating and water heating system sizing and specifications
- Ventilation system (MVHR) specifications (including duct runs, flow rates and Part F compliance)
- Renewable energy specifications; including solar PV, solar thermal, heat pumps
As some of the building techniques in low energy building methods are not yet widely practised, we provide on-going support in the installation of the systems we design and we regularly attend site to ensure the design principles are being adhered to. We also carry out pressure testing and air leakage analysis.
We treat every project as a learning opportunity and carry out post-occupancy surveys to find out how the building is performing (energy efficiency performance) and how the clients are using and experiencing the building (thermal comfort and occupants’ satisfaction). Monitoring our projects allows us to feed this information into our future designs.