Pipes

Insulation for pipes

• Boiler Rooms
• Service Areas (back of house)
• Occupied Areas (front of house)
• Cooling Towers
• Chiller Rooms
• Kitchen Cold stores
• Kitchen Hot water
• Toilet Services

Small to medium Bore (Typical HVAC applications)

For the best result in pipe insulation, Knauf Insulation recommend using Crown Pipe Insulation, a one-piece ‘snap-on’ pre-formed shot-free

noncombustible glass mineral wool insulation of 80 kg/m³ nominal density. The table below sets out the recommended finishes for pipes in a range of locations.

Large Bore (Typical industrial process applications)

For pipes with a bore larger than 250mm, or in areas where access is reduced, Knauf Insulation recommend using Rocksilk Mattress, a noncombustible rock mineral wool faced, on one side with galvanised or stainless steel wire mesh to form a firm but flexible general purpose insulating mattress.

Typical Specification Clauses

Pipework Insulation

P1 Bright Class ‘O’ finish

Pipework to be insulated with Crown Pipe Insulation with bright Class ‘O’ finish, ......mm thick, ensuring that all joints are well butted together.

Longitudinal overlaps to be securely stuck down using the self-adhesive overlap. Butt joints to be covered with suitable self-adhesive tape not less than 50mm wide, bends to be insulated with carefully mitred segments of Crown Pipe Insulation covered with suitable selfadhesive tape. All fittings to be insulated to the same standard and finish as adjacent pipework.

Where the facing is to provide a vapour barrier, all joints must be sealed with adhesive or tape, and any damage to the facing must be repaired with tape or sealant.

P2 Polyisobutylene finish

Pipework to be insulated with Crown Pipe Insulation, ......mm thick, with PIB finish, ensuring that all joints are well butted together.

Longitudinal overlaps to be securely bonded by welding together with white spirit or other suitable solvent. Circumferential butt joints to be overlapped with PIB sheeting by typically 50- 75mm and securely bonded with white spirit or other suitable solvent.

Bends to be insulated with carefully mitred segments of Crown Pipe Insulation covered with PIB sheeting welded together.

All fittings to be insulated to the same standard and finish as adjacent pipework. All overlaps must be arranged to shed water and special care taken when sealing joints in order to prevent the ingress of moisture.

P3 Sheet metal finish

Pipework to be insulated with Crown Pipe Insulation, ......mm thick with ...... finish, ensuring that all joints are well butted together and secured with metal bands at maximum centres of 450mm, with one band at the end of each section. Bends should be insulated with carefully mitred segments of Crown Pipe Insulation, banded into position. All fittings to be insulated to the same standard as adjacent pipework.

Sheet metal to fit tightly over the outer circumference of the insulation with a longitudinal overlap of not less than 40mm, the outer part of the overlap to be secured with self tapping screws or rivets of the appropriate type at centres of not more than 150mm or, 100mm if a weatherproof finish is required or, where appropriate secured with metal bands of suitable type and dimensions.

Circumferential overlaps to be not less than 50mm and secured with self tapping screws or rivets, not less than four equally spaced. At suitable intervals provision should be made to accommodate expansion and contraction. All joints must be lapped “weatherwise” in order to shed liquids where exposed to the weather or if there is risk of liquid spillage onto the surface. All joints should be sealed with suitable sealant. All bends and fittings to be covered with matching sheet metal, tailored to fit and adequately sealed where necessary.

All fittings which may require periodical attention, e.g. valves and flanges, should be fitted with pre-insulated, purpose-designed boxes, which can easily be removed and replaced.

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