This document has been created as an addendum to our PRECON technical data sheet to provide information regarding the application of PRECON waterproofing/vaporproofing membrane in a horizontal application. Following are the typical installation instructions recommended by W. R. MEADOWS. It is important to review each application as there may be situations that may require this procedure to be modified based on the project requirements. If this situation arises, please contact W. R. MEADOWS technical service.
- PRECON waterproofing/vaporproofing membrane: composite sheet membrane comprised of a nonwoven fabric, elastomeric membrane, and W. R. MEADOWS’ patented plasmatic core.
- HYDRALASTIC 836: cold-applied, solvent-free, single-component waterproofing compound used for detailing of PRECON at end laps, penetrations, and repairs.
- BEM: one-component, cold-applied, non-slump waterproofing material that can be used as an alternate to HYDRALASTIC 836.
- MEL-ROL LIQUID MEMBRANE (two-component): two component, 100% solids, cold-applied, non-slump waterproofing material that can be used as an alternate to HYDRALASTIC 836 and is recommended for low temperature installations of PRECON LOW TEMP.
- DETAIL FABRIC: polypropylene, staple fiber, needlepunched, non-woven geotextile fabric used for end laps and penetration details.
- Concrete should be poured within 60 days of membrane installation.
- PRECON may be applied at temperatures down to 40° F (5° C); however, in less than ideal environments or marginal conditions, consider the use of PRECON LOW TEMP below 60° F (16° C). PRECON LOW TEMP can be used in temperatures down to 25° F (-4° C). Please refer to the PRECON COLD WEATHER APPLICATION TECHNICAL BULLETIN for proper installation procedures.
- Prior to the concrete pour, any ponded water, dirt, or debris that has accumulated on PRECON needs to be removed as this could affect the bond of PRECON to the concrete.
- In situations where there is water accumulation behind the membrane during installation, the presence of this water may inhibit proper bond formation at the edge and end laps due to the stress resulting from the constant hydrostatic pressure exerted by this water.
- Care needs to be taken in high-temperature installation situations, as softening of the elastomeric membrane could occur causing sagging.
- Store materials in a clean, dry area in accordance with manufacturer’s instructions.
- Store membrane cartons on pallets and cover if left Keep materials away from sparks and flames.
- Store adhesive at temperatures of 40° F (4.4° C) and above to facilitate handling.
- Do not store at temperatures above 90° F (32° C) for extended periods.
Inspect all surfaces for any conditions detrimental to the proper completion of the work. Surfaces should be structurally sound. Remove debris or any other foreign material that could damage the membrane.
Install PRECON membrane with the fabric side facing towards the concrete floor. Place subsequent rolls of PRECON with a 6″ (152.4 mm) overlap. Remove release paper and roll press into place with a tile type roller.
When a horizontal application meets a vertical application, ensure this overlap is a minimum of 1′ (.3 m) from the base of the wall. Follow the end lap detailing instructions to address the overlap in this area.
Overlap membrane 6″ (152.4 mm). Prior to over- lap, apply BEM, HYDRALASTIC 836, or MEL-ROL® LIQUID MEMBRANE* (two-component) from W. R. MEADOWS in area to be lapped. Roll press membrane into BEM, HYDRALASTIC 836, or MEL-ROL LIQUID MEMBRANE.
Apply BEM, HYDRALASTIC 836, or MEL-ROL LIQUID MEMBRANE 12″ (304.8 mm) wide centered over the termination and while still wet, embed 12″ (31 cm) wide DETAIL FABRIC into the HYDRALASTIC 836 or MEL-ROL LIQUID MEMBRANE and roll press into place. Ensure that DETAIL FABRIC is centered over the termination with 6″ (152.4 mm) on each side of lap edge. Apply additional HYDRALASTIC 836 on all terminations of DETAIL FABRIC.
PENETRATIONS AND PROTRUSIONS
Detail around all penetrations using BEM or MEL-ROL LIQUID MEMBRANE (two-component) from W. R. MEADOWS. Apply BEM or MEL-ROL LIQUID MEMBRANE by forming a fillet around the pipe or protrusion, overlapping the fabric side of PRECON and the protrusion a minimum of 2.5″ (64 mm). If the gap between the protrusion and the membrane is greater than ½” (13 mm), apply PRECON FABRIC TAPE over uncured BEM or MEL-ROL LIQUID MEMBRANE. All penetration and protrusion surfaces must be clean, rust-free, and sound prior to application of BEM or MEL-ROL LIQUID MEMBRANE.
*MEL-ROL LIQUID MEMBRANE is a two-component material, not to be confused with MEL-ROL LM.
For horizontal applications involving a cluster of penetrations, consider the use of HYDRALASTIC 836. Prior to application of HYDRALASTIC 836, prepare the surfaces of the penetrations as above and provide a block out using 2′ x 4′ (.6 x 1.2 m) lumber or other in order to create a “pitch pan” area to receive HYDRALASTIC 836.
SMALL PUNCTURES 1/2″ (12.7 MM) OR LESS
- Apply HYDRALASTIC 836 over the damaged area.
PUNCTURES 1/2″ TO 1″ (12.7 – 25.4 MM) OR LESS
- Apply HYDRALASTIC 836 over the damaged area extending onto PRECON.
- Embed a piece of DETAIL FABRIC into the wet HYDRALASTIC 836.
DAMAGED AREAS GREATER THAN 1″ (25.4 MM)
- Remove the damaged portion of PRECON.
- Apply HYDRALASTIC 836 in a 6″ (150 mm) band onto the fabric face of the PRECON area to be lapped at approximately 60 mils thickness.
- Install a piece of PRECON extending 6″ (300 mm) from the damaged area in all directions and embed into the wet HYDRALASTIC 836. Mechanically fasten to hold into place.
- Apply HYDRALASTIC 836 in a 12″ (300 mm) band centered over the termination and while still wet, embed 12″ (300 mm) wide DETAIL FABRIC into the HYDRALASTIC 836.
- Ensure that DETAIL FABRIC is centered over the termination with 6″ (150 mm) on each side of lap Press DETAIL FABRIC into place to ensure that the HYDRALASTIC 836 has fully wetted out the fabric.
Refer to ACI 302.1R-04: Chapter 4 – Site Preparation and Placing Environment for sub-grade preparation prior to PRECON placement.