Installation - Trex RainEscape

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Installation Videos

Check on the videos below to see step-by-step instructions on installing the Trex RainEscape system.

How to Install an Under Deck Drainage System

Deck design and layout considerations

How to install the downspouts

Installing the trough material

Taping All Joists and Seams

Installing Trex RainEscape WITH House Flashing

Installing Trex RainEscape WITHOUT House Flashing

Installing Wall Flash

Installing Fascia with Trex RainEscape

Installing Trex RainEscape Soffit Lights

Modifying a downspout

Installing a downspout at an angle

How to install cantilevers

Installing a second-story downspout

How to modify downspouts for an obstruction

Installing trough over a double or triple beam

Installing 4×4 inset or flush mount post railing

How to block out a post at the rim joist

How to install 4×4 post flash

Flat blocking for single picture frame

Installing ladder boxing

Using a 2×4 shim method

Installing Trex RainEscape on an extended deck

Installation Photo Gallery

Click on the photo gallery to see step-by-step instructions on installing each component of Trex RainEscape.

For a flush mount post, install the decking first. Install the post applying a small bead of caulk to the threads.

Install the post between two joists spaced 3.5" apart inside to inside.

If installing an inset post, mark the edges of the post on the trough and cut diagonal lines from corner to corner.

Pull up tabs on all four corners. Run a bead of caulk around the posts, no more than 1" above the base of the post.

Slide the trough over the post so it sits flat on the joists.

Tape all seams around the base of the post making a watertight seal.

Use the butyl tape to cover all joists and seams and anywhere a deck screw can penetrate.

Install the adjacent trough and downspout.

Tape all joists and seams.

Install the post.

If using a post sleeve, slide the sleeve down 2"-3" from the top of the joists and run a bead of caulk around the base of the post.

Slide the sleeve down so it sits flat on the joists.

Apply tape around the top of the post flash and wood posts.

Cover with butyl tape to make a watertight seal.

Slide railing over the taped post.

Install Flush Mount and Inset Posts (Railings)

Whether using 12" or 16" joist spacing, tear or cut the front panel of the downspout.

Cut the top flange on the score mark to make a half moon shape.

Place the funnel where you want the gutter line to go on the underside of the deck. Make sure it aligns with the other downspouts.

After all the funnels are in place, install the trough material per the trough installation instructions

Cut a 1" wide X 3/4" tab at center edge of trough and fold the tab down to prevent wicking.

Trough should slope back towards the existing downspout.

Cover the cantilever making sure the trough slopes back towards the downspout and over the existing trough.

Ensure the trough is sloped properly so the water flows to the downspout.

Tape all joists and seams making a watertight seal.

Installing Cantilevers

When installing with flashing, run a bead of caulk to seal underneath the flashing.

Run the bead of caulk across the entire length of the deck.

Lift the trough and apply a heavy bead of the Trex RainEscape caulk between the beams and the joist seam.

Caulking

In fluctuating temperatures, acclimate the trough first. See instructions on acclimating the trough.

Use the 1.5" score mark as a guide and keep it to the left. The smooth, shiny side should always face up.

Unroll the trough using the 1.5" score mark on the inside joist as a guide (on the left). Line up with the second joist.

Put the first staple at the ledger board on the 1.5" score mark side.

Put second staple before downspout. Check to make sure the guideline is inside the joist and then add a third staple through trough and downspout.

Finish stapling every 8" - 10" going from side-to-side until you reach the ledger board.

Cut a 1" wide by 3/4" tab at the center edge of the trough and fold down to prevent wicking.

After installing each trough, test with water to ensure the slope is correct. The water should flow smoothly into the downspout.

After the trough is installed, it may be necessary to use a screen spline roller to create a V shape to help the water flow.

Continuing installing the trough to the left. The trough should cover all exposed wood on the surface.

Trim the excess trough at the seams, keeping overlap so the tape will cover the top of the joists and seams.

Use the Trex RainEscape 4" butyl tape to tape all seams and joists.

Tape all seams and joists.

Do not tape directly on the wood. The trough material should always be below the tape.

Tape works off compression and must be pinched between the decking and the joist to make a watertight seal.

Installing the Trough

Trex RainEscape 4" Butyl Tape is used to protect the joists and seams from moisture

After installing the flashing, use the 4" butyl tape to tape 2" on top of the flashing and 2" on the trough.

When installing a second-story downspout that dumps into the RainEscape system, install the surrounding trough and then tape all the joists and seams making a watertight seal.

When installing an inset post with no post sleeve, cover all the joist and seams connecting the flat blocking trough to the adjacent trough and anywhere a deck screw can penetrate.

When installing the trough, use the butyl tape to cover the overlapping layers to prevent wicking and to seal the screws.

After stapling the downspout in each ladder box, cover all the joists and seams with butyl tape.

Trex RainEscape 4" Butyl Tape is used to protect the joists and seams from moisture

Taping All Joists and Seams

The downspout is designed for a 12" or 16" joist spacing.

The downspout measures 10" tall and fits perfectly into a 2" x 10" joist bay.

Decide whether to use the 12" or 16" side of the downspout.

Cut the pre-scored marked guideline on the downspout with a utility knife or tear by hand.

Once the panel is cut, it will be a half-moon shape.

Place one downspout in each bay opening.

Install the downspout at the rim joist or ledger board.

Make sure the cut side is facing the deck bay.

Downspout should extend about 1" in the gutter.

The downspout funnels water into a standard 5" gutter below the deck.

Installing Downspouts

Extend the trough for decks that are longer than 16".

Tape should not be applied directly to the wood. Trough should always be beneath the tape.

Extended Decks

Trex RainEscape Wall Flash is an EPDM foam that measures 1/4" wide by 1" tall.

Install after the Trex RainEscape system is in place.

Measure and cut a piece of wall flash the width of the deck or the width of the house.

Peel off the backing and adhere the wall flash to in the inside edge of the deck board where it meets the house.

Use your hand to press the wall flash onto the deck board.

Slide the deck board against the house, pushing and compressing the foam strip against the flashing and the house.

Wall flash is designed to keep water, snow, ice, and debris from building up in the first gap between the edge of the first decking board and the house.

Installing Wall Flash

Apply Trex RainEscape butyl caulk between the beams creating a watertight seal.

Install the trough that is adjacent to the beams.

Measure and cut the trough the width of the beams.

Dryfit the trough and staple it into place. Make sure the trough covers all exposed wood and extends over the adjacent joist and 1" into the adjacent bay..

Lift the trough and apply a heavy bead of the Trex RainEscape caulk between the beams and the joist seam.

Use the Trex RainEscape butyl tape to cover all the joists and seams.

Use the butyl tape to cover anywhere that a deck screw can penetrate.

Installing trough over a double or triple beam

Slide the trough beneath the flashing and on top of the ledger board.

Slide the trough beneath the flashing and on top of the ledger board.

Check to be sure the trough is not hitting the face of the ledger board but is sitting on top of the ledger board.

Add a bead of caulk to seal underneath the flashing materials across the length of the deck.

Apply the Trex RainEscape butyl tape covering 2" on the top of the flashing and 2" on the trough.

Make a watertight seal with the tape to prevent water from blowing back during a heavy rain.

Flashing at the House

For a 2" x 12" joist, extend the downspout using a standard gutter downspout and trim to length.

Screw the gutter to the downspout.

The downspout should extend about 1" in the gutter.

If the nozzle extends beyond 1" into the gutter, cut to length.

For a 2" x 6" or 2" x 8" joist, cut the downspout nozzle to length.

Downspout should extend about 1" in the gutter.

Attach the gutter on the underside of the deck frame.

Downspout Extensions and Gutters

Cut out the front panel on the 4" score mark.

Use a utility knife to cut the back side of the funnel.

Cut the funnel from the inside nozzle out to the 1.5" flange.

Cut the funnel.

The funnel will overlap and fit into a smaller bay opening.

Staple the funnel into the bay.

Use the Trex RainEscape 4" butyl tape to cover the slit.

Cut a piece of butyl tape to cover the silt.

Covering the slit makes a watertight seal.

Modifying a Downspout

Soffit Light - Install Wiring

Use Hole Saw to Cut Hole in the Soffit

Pull Down the Wire

Snap Soffit Light Into Place

Soffit Light Installed and in Place

Soffit Light Installed and in Place

Soffit Light

In fluctuating temperatures, the trough needs to be acclimated.

Fold the trough lengthwise.

Create a soft crease down the center of the trough.

Continue folding the trough to create a V down the middle.

Be sure the V goes down the length of the trough.

After the trough is installed, it may be necessary to use a screen spline roller to create a V shape to help the water flow.

After installing each trough, test with water to ensure the slope is correct. The water should flow smoothly into the downspout.

Acclimate Trough

Install the flat blocking as described in the 'flat blocking for breaker board' instructions. Make sure to caulk the seam between the joists and the flat 2x6.

Dry fit the deck board and drill the holes for the railing bolts.

Caulk around the holes with the Trex RainEscape butyl caulk. Put the deck board in place.

Add caulk around the threads when putting the bolt into place. Be sure not to use too much caulk as it will overflow onto the deck or post mount.

Flat Blocking for Flush Mount Post

Install the trough on either side of the breaker board.

Lift the trough and run a bead of caulk underneath.

Measure and cut a piece of trough the width of the breaker board and install over the board.

Dryfit the trough and staple it into place. Make sure the trough covers all exposed wood and extends over the adjacent joist and 1" into the adjacent bay..

Tape all joists and seams.

Flat Blocking for Breaker Board

Install the first joist. Measure 12" OC.

Install the first 2x4 block board at 16" OC from the ledger.

Install the 2x4's every 16" OC and screw the board from the outside of the joist.

Caulk under the trough and along each board junction.

Place a downspout in each ladder.

Staple into place.

Continue stapling the downspouts into place.

Install the gutter line on the underside the deck.

Install the adjacent trough next to the ladder boxing.

Tape all the joist and seams and anywhere a deck screw can penetrate the trough.

Ladder Boxing

Installation Literature

Download the installation guides and instruction sheets below.

Trex RainEscape Complete Booklet Cover – English

Installation Guide

ENGLISH | SPANISH | FRENCH

Instruction Sheet

ENGLISH | SPANISH | FRENCH

Soffit Light Instruction Guide

ENGLISH | SPANISH | FRENCH

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