Energy Efficiency in Timber Homes
Being thermally lightweight, timber frame houses heat up much faster than heavyweight block houses and due to the lower U-value of the timber structure they require far less energy to retain this heat. This means that gas guzzling sources of heat input are switched on less frequently and for shorter periods of time, saving the world from unnecessary CO2 emissions and saving you money.
Timber Houses v Block Houses - A Case Study
The Building Energy Rating (BER) Certificate
U-Value
What is U-Value?
U-Value is the calculated thermal efficiency of a building.
U-Value is defined as the amount of heat / energy (measured in watts) flowing through 1m2 of an element (aka; 1m2 of a wall, roof, floor or window) when the temperature difference between the two faces of the element (ie; the difference between the outside air temp and inside airtemp) is 1 degree Kelvin (W/m2K).
The lower the U-Value the less heat flows through the element and hence the more energy efficient it is.
The Specific Heat Loss Characteristic of a house is a summation of all of the heat flowing through all of the elements plus an allowance for the amount of heat lost by way of air infiltration and ventilation.
U-Value & You: How Building Structure Effects Heating Bills
Block houses are thermally heavy and take many hours to properly heat up. Once heated the inferior U-value of the structure means a high amount of energy is required to maintain the desired temperature / comfort level. Timber Frame houses however are thermally lightweight and therefore heat up much faster, thus using less energy and rendering them ideally suited to todays lifestyle of intermittent and variable occupancy. In addition to this the superior U-value provided by the timber frame design means a far lower level of energy is required to maintain the desired temperature / comfort level, and thus far less needless energy is used, saving the environment from unnecessary CO2 emissions and saving you an average of 33% off your heating bills.
Energy Efficiency in Timber Houses vs Block Houses
How Timber Frame Construction Will Effect the Long-Term Costs of Heating Your Home
Advocates of timber-frame construction have long argued that timber-frame houses are more thermally efficient and therefore more cost effective to heat. However, it has been argued by many brick and mortar advocates that due to new building regulations the same minimum U-value must be achieved in all new build homes regardless of construction method, and therefore thermal efficiency should not be a determining factor when deciding between the two construction methods. Significantly, studies show that in actual practice block homes continuously fall short when it comes to implementing the thermal efficiency calculated in the design stages. This is due in part to poor on-site practices and in greater proportion to the nature of the on-site construction system. The factory based system employed in the construction of timber frame homes allows for far greater accuracy & precision and ensures that u-values predicted in the design plans will actually be achieved in practice.
This assertion is backed below by Bill Quigley's study, "The Comparison of energy use and comfort conditions in Timber Frame and Traditional Block Houses", conducted in 2003 on behalf of COFORD & Nutech Consultants (See Below).
Timber Frame Homes Vs Block Built Homes- A Case Study
In this study Quigley compared the energy efficiency of 3 newly built Timber Frame houses and three similar newly built traditional block houses. Both house types were designed to meet the minimum energy rating (U-Value) as set out by new irish building regulations in light of the findings and recommendations of the Kyoto Protocol. He found that once the houses were finished it was difficult to visibly determine which type of construction method had been used. However, after carrying out a series of tests, the difference in thermal efficiency between the two building types was significantly notable and left no doubt as to which building type was which.
The major conclusion was that the 3 timber-frame houses achieved a higher average house temperature using less energy and at a lower cost than the 3 hollow block built houses.
Significant Findings Include:
- It takes 44% more energy to achieve a 1°C increase over the ambient temperature in hollow block built houses than in timber-frame houses.
- This means that Timber Frame Houses produce 44% less CO2 emissions than Traditional Block Houses, ensuring a green home for you and your family.
- It also means high savings in heating bills. In fact, in this study, energy costs were 32% higher in the hollow block built houses than in the timber-frame houses.
- Furthermore, the amount of energy required to maintain the desired comfort temperature is considerably lower in the timber-frame houses.
The BER Certificate
The emission of Greenhouse gases such as CO2 are the root cause of climate change and advanced global warming.
Construction and use of residential buildings accounts for 30% of our national CO2 emissions.In light of this need for the production of more energy efficient homes, tighter building regulations have since been imposed by the irish government and department of the environment, such as the New Building Regulations Amendment Part 'L', requiring that newly constructed homes lower their energy emissions and U-Values by almost 40% and also meet new renewable energy requirements.
In addition to this, as of January 2009 all new buildings need to get an energy rating certificate known as a BER or Building Energy Rating Certificate. BER assessors calculate the energy performance of the building in order to confirm that it is in compliance with the new regulations.
Similarly any existing buildings that are offered for sale of for rent will need to obtain a certificate, with the aim of making the energy performance of a building transparent and available to potential purchasers or tenants.
*The certificate rates the energy performance of the appliance from A to G with 'A' being the most energy efficient homes and having the lowest energy bills.
For more information on this see the Sustainable Energy Ireland website.
Ramstown Home Insulation
As an optional service, we can supply insulation for your home that is designed to meet the standards laid out in amendment 'L' of the new building regulations. We can also advise you on several upgrade options we have available and put together a tailor-made insulation package designed to help you achieve your desired Building Energy Rating.
We supply a standard home insulation option that meets all the structural U-Value requirements needed to achieve the minimum C1 energy rating as laid out in the L-amendment. Our many upgrade options are available to enable you to improve upon this energy rating and achieve maximum levels of energy efficiency and savings. Under Amendment-L all newly constructed homes must achieve a minimum C1 energy rating as standard. Our upgrade home unsulation option can help your timber frame home to achieve A-level energy ratings - provided it is carried out in accordance with the recommended standards of glazing, heating and ventilation.
Insulation Packages
*The Building Energy Ratings (BER) quoted are achievable when the above standards of insulation are existent
in conjunction with equally efficient standards in glazing, heating & ventilation.
BER Guidelines
Standard Spec Home Insulation | BER Grade Achievable: C1
Structural U-Values Required for this Rating:
Ground Floor U-Value 0.25
External Wall U-Value 0.27
Pitch Roof U-Value 0.20
Flat Roof U-Value 0.16
Additional Recommendations for achieving C1 Rating:
Windows / Doors U-Value: 2.20
Boiler Efficiency: Condensing Gas: 78% Efficient
Ventilation Type: Natural / Without Pressure Test
Electrical Supply: Standard Lighting
Water Heating: Main Heating System
Upgraded Home Insulation | BER Achievable: A3
Structural U-Values Required for an A3 Rating:
Ground Floor U-Value 0.16
External Wall U-Value 0.20
Pitch Roof U-Value 0.14
Flat Roof U-Value 0.14
Additional Recommendations for achieving A3 Rating:
Windows / Doors U-Value: 1.30
Boiler: Condensing Gas Efficiency: 91% +
Ventilation Type: Heat Recovery Ventilation 85% efficient : Air Tightness 2m3/hr/m2 @ 50Pa
Electrical Supply: 100% CFL (Compact Fluorescent Lighting)
Water Heating: 4m2 Solar Hot Water
*Note: Additional factors that are taken into consideration by BER assessors when calculating the energy rating of a dwelling include:
• Glazing Performance
• Structural Air Tightness
• Heating System Efficiency (Boiler etc)
• Heating Controls (Room Stats, TRVs, Zonal Control etc.)
• Ventilation Type (ideally controlled)
• Water Heating Type
• Electrical (Ideally Photovoltaic ie. Solar Powered)
• Building Orientation
For the ultimate R.O.I on your insulation, you may want to avail of our Air-Tightning service (below).
Air-Tight Insulation
If you would like to save up to an additional 35% off your heating bill, protect against structural damage and boost the re-sale value of your timber frame home, air-tight insulation may be the option for you.
Airtight insulation is a process whereby high performance adhesives are used to protect the insulation, creating an airtight barrier that locksin heat, locks out draughts, and saves up to 30% more on your heating bill than you typically pay with standard home insulation. The adhesives used are both durable, and toxin free.
Airtight Insulation prevents Mould and Structural Damage
In a standard insulated house, cold outdoor air comes into contact with warm, moist indoor air within the walls and ceilings of the structure where the insulation is located. When this happens, condensation is formed and the insulation is thus at risk of becoming damp. This creates an environment in which harmful spores can form creating unsightly mould and furthermore pollute the indoor air. Air tight adhesives seal the moist & warm air inside and block the cold outdoor air from entering. In this way airtight insulation prevents condensation, protecting the health of the occupants and preventing the occurrence of what can often be expensive building damage.
Airtight Insulation Reduces Heating Costs and CO2 Emissions
No matter what your standard of thermal insulation may be, draughts come in through the walls and when you turn on your heating, a large proportion of that heat escapes out though your roof. This results in occupants requiring larger fuel tanks, using either electronic, coalfired, or gas guzzling heating appliances (or all three combined) and for extended periods of time, thereby creating high levels of CO2 emissions and equally high heating bills.
If your costly home insulation is to provide you with an adequate return on investment, it needs to be protected. These high performance adhesives create an effective wind-tight seal from without and airtight seal from within. By trapping in this warm air your home requires smaller a fuel tank and fewer heating appliances, turned on for shorter periods of time, thereby reducing your carbon footprint and best of all, saving you money!
Infact, airtight adhesives are proven to save up to 35% off your regular heating bill, and thats before we even take into account the money it saves you by preventing structural damage, as well as the bonus boost in resale value should you ever wish sell youreco-friendly, energy efficient, damp-free home.
Please contact us for more information on this service, or email your house plans to info@ramstown.com to receive a free quote.
Ramstown Timber Frame Company
Ramstown, Gorey, Co. Wexford, Ireland
P: 053 9422 099
F: 053 9422 130
© 2009 Ramstown Developments | Ramstown, Gorey, Co. Wexford | Tel: 053 9422099 / 9421990 | Fax: 053 9422130 | Designed by Divine Monkey