Dáil Éireann Debate, Monday - 11 September 2023
170. Deputy Richard Bruton asked the Minister for the Environment, Climate and Communications if he would consider the replacement of a single-glaze window for stand-alone grant aid in the case of stone houses, for which wall insulation is not feasible; and if he would request the SEAI to model the costs and benefits of such work in those houses in terms of fossil fuel use and carbon emissions. [38918/23]
View answerReplacement of windows in protected or traditional buildings is a complex issue. Alterations to, or the removal of, historic windows within protected structures or buildings in architectural conservation areas will require planning permission.
There are many options available to improve the thermal performance of existing windows including repairs, draught-proofing, secondary glazing and the use of shutters and curtains. Such measures can be used, singly or in combination, to reduce heat loss and increase thermal comfort. Secondary glazing, or secondary windows can also allow for the retention of historic single-glazed windows while considerably improving their thermal performance.
Window repair, even if extensive, should not trigger a requirement under Building Regulations to meet modern standards of energy efficiency, whereas window replacement does. Any new window installed should meet the performance standard specified in Technical Guidance Document (TGD) L. New windows, doors and roof lights should generally have a maximum U-value of 1.4 W/m2K. The NSAI Window Energy Performance Scheme (WEPS) provides a rating for new replacement windows combining heat loss and solar transmittance. Further information on these matters is provided in TGD L.
To support the appropriate upgrade of traditional buildings a new guidance document – ‘Improving Energy Efficiency in Traditional Buildings’ is being developed by the Department of Housing, Local Government and Heritage and will be published later this year. My Department and the SEAI are participating in the steering group overseeing the project. Once available this guidance will be an important resource to support specifiers and contractors in the appropriate energy efficiency upgrading of older, traditionally-built buildings while ensuring compliance with the appropriate building regulations. These guidelines in conjunction with appropriate impact assessment/modelling will also help to inform future grant supports for homeowners.
Where the building in question is not subject to statutory protection (and so long as the proposed works would not materially affect the external appearance of the structure so as to make the appearance inconsistent with the character of the structure or neighbouring structures) there is no legal impediment to the building owner replacing the windows with windows of a higher thermal performance in order to reduce energy loss or as part of a package of building renovation to achieve a specified BER rating. Replacement in such cases should however ensure the design and the materials of the replacements are appropriate. In these situations, windows may be replaced with new double or triple-glazed timber frame units that are compatible with the traditional building. Guidance on this will also be included in the ‘Improving Energy Efficiency in Traditional Buildings’ document.
