Industry Standard Update 074

BS 3632: 2015 Residential park homes – Specification
Date issued: March 2017.

This Industry Standard Update provides an overview of the recently published revised Industry Standard BS 3632: 2015 Residential park homes – Specification, and highlights areas of significant change that the amendments have introduced.

Introduction
During November 2015, the British Standards Institution (BSI) published a revision of BS 3632: 2005⁽¹⁾ – Residential park homes – Specification, which is now withdrawn. The revised standard is now published as BS 3632: 2015⁽²⁾.

BSI recognises that users of BS 3632: 2005 might require time comply with the requirements of BS 3632: 2015. For this reason, there was a transition period of 12 months in which BS 3632: 2005 remained current. BS 3632: 2005 was withdrawn on 30 November 2016.

To allow registered businesses time to carry out internal update training to reflect the technical requirements of the amended standard, Gas Safe Register will inspect to its new requirements from 1 July 2017. However, this should not restrict businesses from applying the specification sooner.

The following is a brief overview of the relevant amendments made to BS 3632.

Section 2: Normative references
References to legislation and current standards have been updated.

Section 3: Terms and definitions
Terms and definitions now includes additional terms such as equivalent area of ventilation and free area of ventilation.

Section 4: Design
Clause 4.10.1
Ventilation shall provide a supply of fresh air for occupants, a supply of combustion air for all non-room-sealed gas appliances and a means of purge venting products of combustion, moisture and noxious odours.

Table 1
Table 1, which provides the minimum intermittent extract ventilation rates, is included in this section.

Table 2
The continuous mechanical ventilation rate shall be the greater of the total ventilation rate (provided in Table 2) and the continuous mechanical ventilation rate calculated using Table 1.

Clause 4.10.4.5
Where passive stack ventilation is used, the required minimum area of background ventilator openings given in Table 3 shall be provided, unless the air tightness of the residential park home is 5m³/h.m² , in which case the minimum area of background ventilators in Table 4 shall be provided.

The total equivalent area of the background ventilators shall be at least equal to the total cross-sectional area of all passive stack ventilator ducts.

The internal cross-sectional area of ducting shall not be less than 12,000mm² and the free surface area of extract terminals shall not be less than the cross-sectional area of the ducting.

Roof terminals shall be installed either on the roof ridge or within 0.5m of the ridge line and shall be sited not less than 1m apart in order to minimise the risk of cross-contamination.

In rooms fitted with an open-flued appliance, the passive stack ventilator can be omitted only if the appliance provides an equivalent level of ventilation when it is not firing.

Clause 4.11
Open and room-sealed appliances shall be sited in order to prevent reversal in the flue system. The selection, installation and operation of any flue system, with all gas appliances and the extractor in operation, shall conform to BS 5440-1⁽³⁾.

Section 6: Internal equipment
Clause 6.5.2
A minimum of two carbon monoxide alarms conforming to BS EN 50291-1⁽⁴⁾ shall be installed in accordance with the manufacturer’s instructions.

Section 7: Installation of services
Clause 7.2
The gas installation shall conform to BS 6891⁽⁵⁾ and BS 5440-1.

Section 9: Notices
Clause 9.2
This has been amended to include minimum dimensions of the gas commissioning notice which are not less than 0.21m and 0.148m.

Summary
As previously stated, this Industry Standard Update is only a brief overview of the information contained in the fully revised standard. Registered businesses should be aware that they have a responsibility to ensure that they are fully apprised of all of the requirements of the whole published standard and their practical application.

Bibliography
(1) BS 3632: 2005 Residential park homes – Specification
(2) BS 3632: 2015 Residential park homes – Specification
(3) BS 5440-1: 2008 Flueing and ventilation for gas appliances of rated input not exceeding 70kW net (1st, 2nd and 3rd family gases) – Part 1: Specification for installation of gas appliances to chimneys and for maintenance of chimneys
(4) BS EN 50291-1 + A1: 2012 Electrical apparatus for the detection of carbon monoxide in domestic premises. Test methods and performance requirements
(5) BS 6891:2015 Specification for the installation and maintenance of low pressure gas installation pipework of up to 35mm (R 1¼) on premises

Download Industry Standard Update 074 here.