8.2.1.4 Building integration
Solar PV technologies shall be securely fixed and not adversely affect the weather resistance of the building.
Foundations and anchor points for stand-alone LZC technologies should be designed by an engineer in accordance with Technical Requirement R5 to withstand the structural forces acting upon them.
The structure to which the LZC technology is attached should be assessed according to its ability to accept the loadings and prevent detrimental effects arising from movement or vibration.
The design of the structure should take account of:
- the self-weight of the LZC components
- imposed loads
- wind loads
- snow loads
- dynamic loading (where relevant)
- the atmospheric conditions ie, coastal locations.
Notching, drilling or chasing of structural components to accommodate service pipes or cables should either comply with Chapter 8.6 ‘Installation and commissioning’ or be designed by an engineer in accordance with Technical Requirement R5.
Fixings, supports, bracketry and mounting frames should:
- accommodate all static and dynamic loads in accordance with the manufacturer’s recommendations
- have adequate protection against corrosion (grade 316 stainless steel is recommended for coastal locations)
- be compatible or isolated where two metals are to be joined to prevent bimetallic corrosion.
All interfaces between the LZC technology and the building should ensure adequate weather resistance (see figure 4), sealed to limit air leakage and prevent moisture from reaching the interior or any part of the structure that could be adversely affected by its presence. The envelope should be weatherproofed using appropriate flashings and fixings. Weatherproofing details that rely solely on sealant are not acceptable. Flashings should be formed from the materials listed in Table 1.
Table 1: Materials for flashings
| Flashing material | Guidance |
|---|---|
| Rolled lead sheet | Minimum code 4. BS EN 12588 |
| Aluminium and aluminium alloys | BS EN 485 and BS EN 573, 0.6-0.9mm thick and protected from contact with mortar by a coating of bituminous paint |
| Zinc alloys | BS EN 988 and 0.6mm thick |
| Copper | BS EN 1172 0.55mm thick and fully annealed. Where two metals are to be joined, they should be compatible and not cause bimetallic corrosion in that environment. Alternatively, they should be isolated from each other |
| Proprietary flashing, including plastic and composite. | Assessed in accordance with Technical Requirement R3 |
To avoid potential surface or interstitial condensation, the design should take account of thermal bridging, particularly where any part of the system, including fixings, penetrates the thermal envelope.
All installations should take into consideration rodent/bird damage, connector corrosion and potential damage caused by follow on trades.
Last updated: 2nd January 2024