Air Tightness Solutions

Useful Information

Build Compliance

SAP Assessments Part L1A – New Residential Houses

New residential buildings must comply with Part L1A of Building Regulations, which stipulates that SAP 2009 assessments must be undertaken, and submitted to Building Control prior to the start of any works on site. All SAP assessments must be undertaken by accredited Energy Assessors. Upon completion of the build, the SAP assessment is upgraded to an As Built SAP calculation incorporating any changes from the initial design.

SAP Assessments Part L1B – Existing Residential Houses

Our nationwide team of Energy Assessors can also carry out the required energy calculations to demonstrate compliance with Part L1B, which applies to existing residential buildings. We provide SAP Calculation for converted dwellings, extensions and conservatories. SAP Calculations for converted dwellings The conversion SAP calculation assesses the thermal efficiency of the proposed building fabric, together with the energy requirements of the heating, lighting and hot water systems. However, compliance with any prescribed limits on carbon dioxide emissions is not currently required. SAP Calculations for extensions and conservatories For extensions, two alternate extension SAP calculations are produced: a notional SAP calculation based on the existing property with a conventional extension to the dimensions as proposed. Also, a second extension SAP based on the proposed extension.

SBEM Assessments Part L2A – Non-Domestic buildings

SBEM calculate the amount of energy used by a non-residential building, through heating, air conditioning and lighting.  The amount of carbon dioxide the building emits is also calculated, before then assigning the building a rating between 1 and 100. The closer to 100 the rating is, the more energy efficient the building is deemed to be.

There are three parts to an SBEM Calculation:

  1. a) Design Stage
  2. b) As Built
  3. c) Energy Performance Certificate (EPC)

Energy use in buildings varies significantly so it’s difficult to predict the result of an SBEM.

Lighting is one of the biggest influences.

If your building is greater than 500m² consider your Air Tight Barrier Line early.

You might additionally require:

Level 5 SBEM for projects with atriums, a complex ventilation system or an automatic blind control system.

Dynamic Simulation Modelling for achieving the HEA 3 credits in BREEAM or the building has an overheating risk.

There are a number of different types of buildings that will need an SBEM calculation. These include:

An SBEM Calculation has 3 parts:

  1. a) Design Stage
  2. b) As Built
  3. c) Energy Performance Certificate (EPC)

Energy use in buildings varies significantly so it’s difficult to predict the result of an SBEM.

Lighting is one of the biggest influences.

If your building is greater than 500m² consider your Air Tight Barrier Line early.

You might additionally require:

Level 5 SBEM for projects with atriums, a complex ventilation system or an automatic blind control system.

Dynamic Simulation Modelling for achieving the HEA 3 credits in BREEAM or the building has an overheating risk.

Build Sustainability Performance

Air Leakage

What is Air Leakage?

Air leakage is the uncontrolled flow of air through gaps and cracks in the fabric of a building, caused by wind across the building or stack effect within the building. This is not to be confused with ventilation, which is the controlled flow of air into and out of the building, through purpose built ventilators that are required for the comfort and safety of the occupants.

Too much air leakage leads to unnecessary heat loss, discomfort to the occupants and not only increases your carbon footprint but ultimately means more costs for you.

Why is Reducing Air Leakage important?

Heating buildings involves burning fossil fuels resulting in CO2 emissions, increasing green house gas and contributing to Global Warming.  Reducing the air leakage of a building decreases the CO2 emissions and also your heating bills. Eliminating those drafts also improves occupier comfort. With recent improvements in the insulation of walls and glazing, the proportion of air leakage through gaps and cracks in the building fabric has become more significant, as a well insulated building will not retain heat, unless it’s correctly airtight.

The UK Government pledges to halve CO2 emissions by 2025.  It is predicted that we need to reduce carbon emissions attributable to energy consumption in new and refurbished commercial buildings by approximately 3.5% per annum, if we are to be close to achieving such targets. With an apparent 40% of CO2 emissions attributed to the existing housing stock and existing builds making up an estimated 70% of the housing stock in 2050, it is imperative that effective action is undertaken in both the commercial and domestic sector for existing as well as new builds.

Sound Insulation Testing

What is Sound Insulation Testing?

Sound insulation testing is the method used to measure the resistance of sound provided by an element of a building (such as a floor or wall) between dwellings. It essentially measures the effectiveness of the sound proofing treatment installed as part of a build or property development.

Airborne Tests – These tests are carried out on party walls and floors/ceilings between dwellings. An airborne test measures levels of sound transmitted through the air. We use a loudspeaker that produces white noise on one side of the partition, and measure with a decibel meter on the other side how much sound is lost through the partition.

Impact Tests These are only carried out on separating floor/ceiling divides between dwellings. An impact test measures the levels of noise transmitted directly through a separating construction as a result of impact. We use a tapping machine, which drops metal hammers onto the floor to create impact noise. We then measure the amount of sound that passes through the partition with a decibel meter on the other side of the divide.

Testing can only be completed on ‘habitable’ rooms. Habitable rooms can be bedrooms, lounges, living rooms and open plan kitchen/ living spaces.

Why is it important?

It has been a mandatory part of the Building Regulations for new build and refurbishment projects since Approved Document E was revised in 2003.