Sealants and Profile Fillers

At shallow pitches the side and end laps of profiled sheeting require effective seals as a means of achieving a weathertight building envelope. Recommendations for the position and application of sealants are given in the relevant roof material chapters, the recommended sealant types are given in the following corresponding tables:

profiled metal weathersheet and composite panels, (Chapters 3 and 4), Tables 8.1–8.3; Table 8.1 Profiled steel sheets https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">

Sealant type

Life (years)

Profiled steel sheets

Metal liner

Side lap

End lap

Flashing

Side lap

End lap

Preformed sections

PIB butyl

20

Y

Y

Y

Y

Y

Cross-linked butyl

20

Y

Y

Y

Y

Y

Self-adhesive tapes

EPDM foam

20

C

C

N

C

C

PVC foam

15

C

N

N

C

C

Polyethylene foam

15

C

N

N

C

C

Aluminium backed

N

N

N

Y

C

Gun applied sealant

Silicone (neutral cure), 1 part ^*

20

C

C

Y

C

C

Polyurethane, 1 part ^*

20

C

C

Y

C

C

Butyl

10

C

C

Y

C

C

Grease

N

N

N

N

N

Y Recommended.

N Not recommended.

C Check suitability with sealant manufacturer and profile manufacturer’s recommendations.

*

Primer may be required.

Table 8.2 Profiled aluminium sheets https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">

Sealant type

Life (years)

Aluminium profiled sheet

Aluminium liner sheets

Side lap

End lap

Flashing

Side lap

End lap

Preformed sections

PIB butyl

20

Y

Y

Y

Y

Y

Cross-linked butyl

20

Y

Y

Y

Y

Y

Self-adhesive tapes

EPDM foam

20

C

N

N

C

C

PVC foam

15

N

N

N

C

C

Polyethylene foam

15

C

N

N

C

C

Aluminium backed

N

N

N

Y

C

Gun applied sealant

Silicone (neutral cure), 1 part ^*

20

C

C

Y

C

C

Polyurethane, 1 part ^*

20

C

C

Y

C

C

Butyl

10

C

C

Y

N

N

Grease

Y

Y

Y

C

C

See footnotes to Table 8.1.

Table 8.3 Miscellaneous sheets https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">

Sealant type

Life (years)

Gutters

Rooflights Insulation boards

Steel

Aluminium

PVC

GRP

Board to T bar

Preformed sections

PIB butyl

20

Y

Y

Y

Y

N

Cross-linked butyl

20

Y

Y

Y

Y

Y+tape

Self-adhesive tapes

EPDM foam

20

C

C

C

C

N

PVC foam

15

Y

Y

C

C

N

Polyethylene foam

15

Y

Y

C

C

N

Aluminium backed

15

C

C

C

C

Y+cross-linked butyl

Gun applied sealant

Silicone (neutral cure), 1 part ^*

20

Y

Y

Y

Y

C

Polyurethane, 1 part ^*

20

Y

Y

Y

Y

N

Butyl

10

N

N

C

C

N

See footnotes to Table 8.1.

fibre-cement weathersheets (Chapter 5), Table 8.4. Table 8.4 Profiled fibre-cement sheets https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">

Sealant type

Life (years)

Profiled sheet

Liner sheet

Side lap

End lap

Flashing

Side lap

End lap

Preformed sections

PIB butyl

20

Y

Y

Y

Y

Y

Cross-linked butyl

20

Y

Y

Y

Y

Y

Self-adhesive tapes

EPDM foam

20

C

C

C

C

C

PVC foam

15

C

C

C

C

C

Polyethylene foam

15

C

C

C

C

C

Aluminium backed

15

C

C

C

C

C

Gun applied sealant

Silicone (neutral cure), 1 part^*

20

C

C

C

C

C

Polyurethane, 1 part ^*

20

C

C

C

C

C

Butyl

10

N

N

N

N

N

See footnotes to Table 8.1.

Sealants are also essential to the formation of effective vapour control layers (VCL) necessary for limiting the risk of interstitial condensation.