Guide to Conversion of Traditional Buildings

6.4 Insulation of pipes, ducts and vessels

Mandatory Standard

Standard 6.4

Every building must be designed and constructed in such a way that

temperature loss from heated pipes, ducts and vessels, and temperature

gain to cooled pipes and ducts, is resisted.

Limitation:

This standard does not apply to:

a) buildings which do not use fuel or power for heating or cooling either

the internal environment or water services

b) buildings, or parts of a building, which will not be heated, other than heating provided solely for the purpose of frost protection, or

c) pipes, ducts or vessels that form part of an isolated industrial or commercial process.

6.4.1 Application of standard to conversions

In the case of conversions, as specified in regulation 4, the building as converted shall meet the requirements of this standard in so far as is reasonably practicable, and in no case be worse than before the conversion (regulation 12, schedule 6).

6.4.2 Commentary

Where a traditional building is to be converted and heated or cooled, suitable insulation of the heating and cooling systems will be required. It is acknowledged that this may not always be possible, for example where services pass through elements of structure.

All guidance associated with section 6.4 is now provided through a link to the Domestic Building Services Compliance Guide for Scotland. In this guide, section 6.4 is largely represented by section 9: Vessel, pipework and duct insulation.

6.4.3 Issues to be considered

Typical risks in the conversion of historic/traditional buildings

1. Insertion and insulation of services

Where buildings are converted and newly serviced, there is a risk that the new or upgraded service installation could damage or otherwise impact the historic fabric. This risk is increased by the need to insulate services and thus enlarge the scale of all items. Impacts can include:

• Covering or obscuring of historic features or details.
• Causing direct damage during installation or subsequent maintenance.
• Inducing staining through leaks or condensation.
• Creation of dirt traps where services are run close to the surface.

2. Upgrading existing services

Where buildings are converted, there may be existing services which represent specific risks:

• Hard to access services which are uninsulated or inadequately insulated should be upgraded, but this may cause undue damage or disruption.
• Cold water pipes or ducts in previously unheated and well ventilated areas may represent a condensation risk once these areas have been insulated and made warmer and more airtight.
• Conversely, existing water pipes in spaces now outside the insulated envelope (for example, in insulated loft spaces) represent an increased risk of freezing and in these cases insulation is critical, along with adequate access where possible.
• Cupboards and other service cavities which accommodated services previously may not be large enough to accommodate all services when adequately insulated, so adjustments may be required.

3. Design of routes

Inadequate design or forward planning of services routes can mean routes are left to site operatives who may not have the necessary understanding of the special needs of historic buildings

4. ‘Cooler’ historic buildings

Where traditional or historic buildings are not heated to modern standards, the heat loss from heated pipes, ducts and vessels will increase, highlighting the need to provide adequate insulation.

5. Overheating

In warmer weather, uninsulated hot water pipes represent an increased risk of overheating.

6.4.4 Recommendations to meet the standard

Where improvements to fabric performance are difficult to achieve, it is important to optimise improvements in other areas. Heat loss, energy wastage and condensation risk from uninsulated pipework should be avoidable in most situations with careful planning and design.

In projects involving traditional and historic buildings, it is important to ensure all new and existing service routes are carefully considered at the design stage to enable optimisation of energy efficiency while minimising undue physical and visual impacts on the building’s fabric and character.

There is an inherent risk with routing services through historic buildings, and the need for insulation exacerbates these risks. If it is not possible to re-route services, the best way to minimise this technically is to use thinner, high-performance insulants with lower thermal conductivities. While higher performing insulants may be more costly, it may be possible to use them only in areas of particular risk or visual impact.

Consideration should be given to condensation and freezing risks to pipework. Cold pipework within new warm areas may now be prone to condensation. Conversely, pipework that now lies outside of warm areas after insulation improvements may subsequently be at risk from freezing. Note that insulation materials or systems may need to be vapour-proof to avoid condensation saturating the insulation and surrounding areas.