VIP King
02-08-2005, 09:05 ِAM
Curtain Wall Termination at Soffit — Detail
The termination of a curtain wall at a cold soffit is an area often overlooked with respect to air sealing and continuity of thermal insulation. Provide a continuous metal closure from the shoulder of the lowest horizontal rail back up to the underside of the slab. This ensures that gaps between the backpan and the mullion and the mullion tubes themselves are well sealed. Thermal insulation to the backside of the wall, particularly the mullion tubes, should be continuous. The end of the wall is often under-insulated due to the desire to maintain a sight-line matching the lowest snap cap. Air Barrier continuity between the underside of the slab and the lower rail of the curtain wall is provided by the membrane supported by a sheet metal backing sheet. The backing sheet is mechanically fastened to the underside of the slab, the mullions and the lower rail.
In high humidity buildings a heated soffit should be considered to avoid condensation in the assembly.
Thermal Barrier continuity is provided by semi-rigid insulation held with straps or stick pins tight to the air barrier closure to prevent air circulation between the air barrier and the :D :D insulation.
Vapour Retarder function is provided by the inherent resistance of the materials.
Water Penetration control is provided by the sealed membrane and the drainage inherent in the curtain wall system.
Continuous Metal Membrane Support
A continuous sheet metal closure connecting the shoulder of the lowest horizontal rail to the underside of the slab ensures full support to any membrane work and bridges any small gaps such as that between the backpan and the side of the mullion.
Membrane
Either a continuous membrane or membrane strips at all seams and terminations completes the air seal between the slab and the end of the curtain coolguy.gi wall.
Metal Backpan
The preformed metal backpan is glazed into the curtain wall framing much as a piece of glass. The backpan detailing at the soffit is the same as at typical spandrel conditions. Where the insulation thickness does not provide full coverage of the sides of the backpan wider strips of insulation should be provided about the backpan perimeter to enhance condensation resistance.
Suspended Metal Soffit
In many cases the section of stick built curtain wall terminating at a soffit actually extends up past two floor-slabs and is fixed against vertical movement at the second slab level. As such differential movement between the wall and the first floor slab and suspended soffit will be maximized. As shown, the suspended soffit should not fix directly to the curtain wall.
Semi-Rigid Insulation
Semi-rigid insulation as used on the underside of the soffit should be continued along the back and end of the curtain wall. Where the thickness of the insulation at the termination of the curtain wall is restricted even a very thin layer of rigid insulation can be very effective.
Termination Pane:cool: l
The formed metal termination panel should ideally contain a drip edge and integrated with the suspended metal soffit.
http://www.cmhc-schl.gc.ca/en/imquaf/himu/images/detail2_s_e.gif
drink.gif
The termination of a curtain wall at a cold soffit is an area often overlooked with respect to air sealing and continuity of thermal insulation. Provide a continuous metal closure from the shoulder of the lowest horizontal rail back up to the underside of the slab. This ensures that gaps between the backpan and the mullion and the mullion tubes themselves are well sealed. Thermal insulation to the backside of the wall, particularly the mullion tubes, should be continuous. The end of the wall is often under-insulated due to the desire to maintain a sight-line matching the lowest snap cap. Air Barrier continuity between the underside of the slab and the lower rail of the curtain wall is provided by the membrane supported by a sheet metal backing sheet. The backing sheet is mechanically fastened to the underside of the slab, the mullions and the lower rail.
In high humidity buildings a heated soffit should be considered to avoid condensation in the assembly.
Thermal Barrier continuity is provided by semi-rigid insulation held with straps or stick pins tight to the air barrier closure to prevent air circulation between the air barrier and the :D :D insulation.
Vapour Retarder function is provided by the inherent resistance of the materials.
Water Penetration control is provided by the sealed membrane and the drainage inherent in the curtain wall system.
Continuous Metal Membrane Support
A continuous sheet metal closure connecting the shoulder of the lowest horizontal rail to the underside of the slab ensures full support to any membrane work and bridges any small gaps such as that between the backpan and the side of the mullion.
Membrane
Either a continuous membrane or membrane strips at all seams and terminations completes the air seal between the slab and the end of the curtain coolguy.gi wall.
Metal Backpan
The preformed metal backpan is glazed into the curtain wall framing much as a piece of glass. The backpan detailing at the soffit is the same as at typical spandrel conditions. Where the insulation thickness does not provide full coverage of the sides of the backpan wider strips of insulation should be provided about the backpan perimeter to enhance condensation resistance.
Suspended Metal Soffit
In many cases the section of stick built curtain wall terminating at a soffit actually extends up past two floor-slabs and is fixed against vertical movement at the second slab level. As such differential movement between the wall and the first floor slab and suspended soffit will be maximized. As shown, the suspended soffit should not fix directly to the curtain wall.
Semi-Rigid Insulation
Semi-rigid insulation as used on the underside of the soffit should be continued along the back and end of the curtain wall. Where the thickness of the insulation at the termination of the curtain wall is restricted even a very thin layer of rigid insulation can be very effective.
Termination Pane:cool: l
The formed metal termination panel should ideally contain a drip edge and integrated with the suspended metal soffit.
http://www.cmhc-schl.gc.ca/en/imquaf/himu/images/detail2_s_e.gif
drink.gif