Grasscloth Engineering and Logistics – Technical Details Post

Grasscloth is a natural material that cannot be matched from strip to strip, so all the seams will be visible . In addition, there is usually a slight but noticeable color difference between strips / panels (called shading or paneling ) . So it’s important to plot the layout of the strips to give the most visually pleasing overall look. Usually this means balancing the width of strips so they are all equal , at least on the same wall . We call this engineering .
This wall presented particular challenges , due to the widths of the elements. Grasscloth comes 36″ wide . You can use your straightedge and a sharp razor blade and trim it down to any width you want.
The width of both the large wall spaces to the right and left of the bank of windows was 34.” The width of each window was about 35.” The width of the two spaces in between the windows was 7.”
So you’d think I could trim my panels on either side of the windows, and then over the windows, to about 34″-36″ – give or take a few inches (or fractions thereof).
But that would leave me with two 7″ wide strips between these 35″ panels. Although the look would be uniform and mirror-image from the center outward, moving from right to left you’d have: 35,” 35″, 7,” 35,” 7,” 35,” 35,” … those 7″ breaks were just not going to look right.
One option was to determine the width of the wall (189″) and make each strip an equal width. This worked out to six strips, each at 31.5″ Not good, because this would mean a seam down either far side. And since those sides were 34″ wide, that would mean a 31.5″ wide strip and a strip 2.5″ wide. Not attractive at all, and it would use up an extra strip of wallpaper.
This six strips @ 31.5″ wide scenario might also land with a seam smack in the middle of those 7″ wide interludes in between the windows. Not attractive at all.
So I decided to make the two outer strips 35″ wide. That left 119″ of wall space above the windows to be covered with wallpaper. Do some math and you get four panels of 29.75″ wide. This gave a balanced and uniform look to the area over the windows, and also prevented seams from landing between the windows.
Moving right to left, I cut and hung the full length outer strip first. Then I cut and hung the strip over the window on the right. Then I measured to find the centerpoint of the window in the middle. Turns out it was a bit less than 29.75″ away. So I trimmed that next over-window strip accordingly.
Once that was in place, I measured from that center point above the middle window out to where my left full-height panel would fall, 35″ out from the wall. Took the resulting measurement and divided by 2. Lo and behold, each of the next two panels over the window was going to be a bit wider than 30.” No problem. No one (but a paperhanger or maybe an engineer) is going to notice a 1/4″ or even a full 1″ difference in widths between this strips over the windows.
Another thing to point out … it’s important that I took measurements before cutting these strips for this second left-hand section. Because, since grasscloth comes at 36″ (and walls can be wonky), if my strips had been narrower (say, 28″), that last full-height panel on the left might have ended up needing to be 37″ wide – and that wouldn’t work because it only comes 36″ wide – plus you need at least 1/8″ to wrap around the corner.
Luckily I had the flexibility to be able to trim the panels over the windows to any width needed, to accommodate all this.
If you’ve followed all this so far, let me also toss in that we also need to figure how to get paper in between those windows. More on that below.
In this scenario, I’m moving from right to left.

Area beneath the windows needs to be treated in the same way, and preferably with widths that match what’s going on above the windows. In addition, it’s tricky because after you move across 12′ of wall space, the strips above and below the windows are going to twist and torque out of shape, so that last full-length panel on the far left might not butt up perfectly with the last strip under the windows.

The grasscloth is black , and my wallpaper primer is white . It’s common for teeny gaps to appear at the seams . In this case, it’s likely that white wall would peek out from those gaps. So I like to stripe under where the seams will fall with dark (diluted) paint . This takes measuring , plotting , and also a heat gun to get the paint to dry before the wallpaper hits it, to avoid staining. You can do a Search here to read more about this technique .
Now let’s talk about getting wallpaper in between those windows.
As you can see in the photo, if I hang a 30″ wide strip, a whole lot of paper is going to be cut off and thrown away. Also, a whole lot of sticky, pasted paper is going to bump against that window molding and maybe even the window glass. A lot to clean up! And unwieldy, to boot.
My solution was to stop the wallpaper just a little below the tops of the windows. Then I would patch in a 7″ wide strip in between the windows. This is trickier than it sounds, because, if it were a paper wallpaper, I could simply cut along a design motif and overlay the 7″ wide piece. But grasscloth is thick and overlaps don’t look good. Also grass has no design elements , and the reeds of grass don’t necessarily fall perfectly horizontal , and even if you cut everything perfectly true to square , if the window molding is a teeny bit off-plumb , then your edges won’t butt up perfectly.
So that’s a good reason for striping the black paint under where the butt join will occur.

Same thing for the sections under the windows. I measured and positioned the strips so that the top edge (which I had trimmed to be perfectly horizontal) fell between the narrowest part of the windowsill molding, for less visibility.
I admit, instead of butting the two pieces, here I did overlap the 7″ wide strip about 1/4″ onto the piece under the window, right at that narrow junction. It’s only about 3″ wide, and I figured no one is going to be examining it that closely, anyway. This saved me about a half an hour of measuring, trimming, testing, repeat, repeat.
This is my second window interlude, and by this time I had realized that it’s hard to trim stiff grasscloth around intricate moldings precisely . So I used paint to fill in the edges around the window molding, just in case there might be any gaps between the grasscloth and the molding, so you would see black instead of the white molding paint. I did this with a small sponge; if I had used an artist’s brush it would have been a bit neater and tighter to the conforms of the molding. But sometimes you’ve gotta relax and realize that no one’s going to be scrutinizing the insides of moldings below shin-level.

Area over windows finished, with drapes back in place.
Turns out this particular grasscloth is so uniform in color (quite unusual, I will add), that you can’t really see the panels , nor their equal widths , anyway. I’m still glad I took the time to do all this math and trimming.

Area below the windows, done. That last seam on the left bears some explanation, too. Moving across the top of the windows, I measured that that last strip – the full-length strip – would need to be exactly 35″ wide. It butted up nicely to the last strip above the windows.
But, due to twisting , shifting , expansion , unlevel and unplumb walls and ceilings , and other factors, there is a really good chance that that last 35″ wide strip would not butt up perfectly with the last 30″ wide strip under the window . So I planned to splice these last two strips together.
Yeah, the drapes are hanging there, I coulda overlapped the two strips about 1/2″ and the drapes would have covered it. With a thin wallpaper, I probably would have done this. But grasscloth is thick, and an overlap would be visible , and also the adhesive / paste can’t be trusted to adhere as well to grass as it would to paper .
So I plotted for a splice. Instead of trimming my last strip under the window to 30″ (read above), I trimmed it to 32″ wide. That way, when I hung the last full-length strip to the left, which was 35″ wide, it overlapped the piece under the window by a few inches. Then I did a double cut and spliced the two pieces. See below for details about that technique.

Grasscloth is 36″ wide, and this wall area is wider than that. So two strips were needed. This means you’re going to have a seam, and since grasscloth seams are always visible, it looks best to plot to have the seam fall down the center. It uses more wallpaper to do this, but it looks much better than having, for example, a 36″ wide strip next to an 8″ wide strip.
As mentioned above, in case you get thin gaps at the seams, a dark stripe of diluted craft paint under where the seam will fall, will prevent white wall from showing through.

Rounded / bull-nosed edges and corners have been popular in new construction for at least 10 years. I wish they’d go away. They’re very difficult to trim around, and hard for the paper to conform to and adhere to.
It’s very hard to trim around that rounded edge, because the paper is hanging over and blocking your view, because grasscloth is thick and stiff and your fingers can’t feel through it, and because the edges aren’t necessarily true and plumb so a laser level or other level won’t help you much.

I use this little gadget as a trim guide. It’s actually a small section of the same corner bead material that drywallers use when they assemble these walls. Cut to about 1″ long and notched in different places where you might trim along the edge of the wall.
It’s intended that you place your trimming knife in one of the notches and slide the gizmo along the edge and make your cut. I find that awkward and also inaccurate. So I prefer to use the notches as a guide and mark where I plan to trim with a pencil. Since this wallpaper is black, I used this marking pencil from my home sewing kit instead. Chalk might work, but I was afraid it might now wipe off completely.
The pink pencil line was barely visible, but it was enough for me to use a scissors to trim along the grasscloth. I like this better than using a razor blade as I can see better, and also less chance of scoring into the primer or wall. Which raises its own set of issues – do a search here to find previous posts.

Inside view of the trim guide.

Finished arch. Note the four panels of equal width above the arch. And two flanking full-height panels also the same widths.
I was lucky that there was no pattern to match, so I was able to butt my two flanking strips right up to the edge of the bull-nosed corner. No trimming needed! Then I measured the remaining width between these two strips (the area over the arch), divided by four, and cut four strips of equal widths.
I hung the two on the left, and then one on the far right. This left one strip still to be positioned to the right of center. So the pieces are going to meet over the arch, rather than the last strip falling in a corner.
Same as the last strip under the window (discussed above), it’s really difficult to get your last piece to fit in here perfectly. I’ve done it, but it takes a lot of measuring, trimming, testing, retrimming, and often starting all over again.
So I did a double-cut / splice.

A double cut involves cutting each strip an inch or so wider than it should be, and overlapping the two. Then you take a straight edge and sharp razor blade and cut through both layers. This handy tool is a wonderful non-slip guide for this process. It was invented by an installer colleague in the Wallcovering Installers Association ( WIA ) and she has them fabricated in various lengths (along with other cool tools ) and sells them on-line. Contact me if you’re interested.
Anyway, it takes a lot of strength to cut through two layers of grasscloth, so somewhat difficult for lil’ ol’ me.
You also want to be sure to not cut / score into the wall, because the tension of drying wallpaper can tug at the wall and cause it to actually come apart, leaving an open seam that’s difficult to repair.
So you’ve got to put some padding under the wall where the cut will take place. I use special strips of polystyrene (hard but flexible plastic) to pad the wall. Also invented by a colleague in the WIA , who also sells other cool tools and supplies. Contact me if you’re interested.

This black grasscloth was printed on a white substrate. If the seams aren’t absolutely tight, there can be worries about the backing showing through to the front. So sometimes we’ll take a piece of chalk or pastel (never oil pastel or permanent markers because they bleed and stain ) and run it along the edge of the paper – from the back, and taking care to not get chalk on the surface.
I do this frequently with dark papers ( do a search here to see previous posts ) but opted not to do it with this grasscloth. It wasn’t necessary, and might have stained the porous reeds of the grass. It was beneficial, though, to have striped dark paint on the wall under the seams, as mentioned above.

Ugh. Grasscloth comes 36″ wide, and this section of wall is 38″ wide. It’s not visually pleasing, nor is it easy from an installation point of view, to have a 36″ wide strip next to a 2″ wide strip. Or to use scraps and put a 25″ wide strip next to a 13″ wide strip.
So best to plan two strips of equal widths. Two strips, each 19″ wide, with the seam down the middle.
Actually, the strip on the left was 19″ wide, but I trimmed the strip on the right to 21″, because I like the wallpaper to extend 2″ over the top of the door molding. This provides a more stable surface in case of shifting foundation or walls, and less likelihood (knock on wood) of the seam opening up should the house / drywall experience shifting.
Note that design “rules” caution against seams down the middle of spaces. But it would have been more visually distracting (and used up more paper) to have made three strips of each 12.75″ wide. And would have looked even dumber to have used scraps left from other walls and put together two strips of disparate widths.
So the homeowner and I discussed during our initial consultation , and she was happy with the center seam. Once it was all finished, this particular grasscloth was so even in tone that you barely see the seams, anyway. Win-win!
This did use up additional paper, though, as noted in a previous photo above.

Wallpaper on a Window Valance

I hung a beautiful grasscloth in the West U. living room of this empty-nester couple a month ago. They were putting the room back together, including hanging the curtains. This window valance had been covered with padded fabric which matched the drapes. Since the drapes are being changed, the valance no longer worked. The couple thought that the valance would look better covered in the same material as the walls.

So … I brought the valance home, along with some left over wallpaper scraps, and covered it.

The photo is deceptive – the thing is about 7′-8′ long. At first I thought I could take it to work with me and do it while I was waiting for primer to dry, for instance. But it’s way too big and loppy to haul into someone else’s home and, would, of course, take more time than anticipated.

So it sat in my garage for a couple of weeks, until I finally found a spare moment (three hours, actually) to pull out my tools, set up my table, get out the measuring tape, and slap some paste on that puppy.

The homeowner had removed the upholstery and the padding, and hammered the staples down as flat as possible. Then I sealed the wood with oil-based KILZ Original stain blocker, to prevent any wood sap from bleeding through the wallpaper. Since wallpaper paste won’t stick to most oil-based products I followed that with a coat of wallpaper primer (Ultra Prime, Pro 977 by Roman’s). On the driveway under the June Houston sun, that didn’t take long to dry. 🙂

Then some careful measuring to get panels of equal width, pasting, and applying the grasscloth to the wooden frame. I used a special “super glue for wallpaper” (clear silicone caulk 🙂 ) for the edges, to be sure the grasscloth would be able to grip on to the uneven and rough wooden surfaces.

I was pleased with the way it turned out. And I know the homeowners will be happy to get the valance up on the wall, their curtains up, and their room put back together and ready to enjoy.