Cavity Trays Ltd

Type U Cavitray
for undersills

in brief...

  • Shaped DPC cavitray
  • Integral sill alignment facility
  • Removable front section
  • Ensures consistent build detail
  • Selection of profiles
  • Traditional or timber-frame construction

The DPC has not been returned in the bedding course immediately under the sill, but instead is terminated approximately 75mm lower.  This approach permits collected water to be safely discharged via Type W weepvents.
This profile promotes water evacuation of the cavity and breathing of the cavity void - a benefit which is not possible if the DPC is returned at a higher level.

 

 

material
2mm black polypropylene with Securtex top surface finish.

colour
Black polypropylene.

installation/sitework
Type U undersill cavitrays should be handled and bedded in position, in the same manner as conventional DPCs and lintels.  Do not dry bed.  Locate undersill cavitray so that the back vertical section (with or without integral insulation) always rises against the skin.  The front of the undersill cavitray must be fully bedded on mortar and soundly bonded to the outside skin.  The rear of the tray must similarly be fully bedded and bonded to the inside skin.  Following firm location in the correct position, traditional construction of the sill in masonry or tile may proceed.

Always solidly construct using a suitable mortar.  Ensure stopends

 

 are in position.  The front lip should function as a guide against which the sill edge us aligned.
The front section of the Tupe U undersill cavitray is removable and the break-joint should be positioned so that it is slightly forward of the faceline of the exterior skin.  It is recommended that an expansion gap (6mm) is left between the top of brick or tile sill and the underside of the frame sill.
Seal at a later date using Siliconbond.  Remove guide lip following setting of mortar, if desired.  At all times observe the recommendations of the NHBC Performance Standards.  In case of the rendered wall, the undersill 

  
             		cavitray should be of a size so that the removable front section break-line is forward of the rendered face.

ordering
See inside back cover for immediate service throughout the United Kingdom.  Merchant distribution netowrk.

related products and
applications
For venting below pre-cast sills, see Type W weepvent, Euroweep-vent and Small weepvent.  See Siliconbond for flexible caulking which may be applied to expansion gap between window sill and sub-sill.

 

  

Cavity Trays     phone 01935 474769 fax 01935 428223 email enquiries@cavitytrays.co.uk