Posts Tagged ‘color difference’

Run Numbers – Re Previous Post

May 15, 2021
Run numbers are important!

Re my previous post, before I visited, the homeowner had purchased 8 rolls (4 double roll bolts) of paper. This was just exactly enough (12 strips) for the headboard wall, but I told him to order 16 more to do the rest of the room. The new paper came in a different run. So we had Run 16 for the headboard accent wall, and Run 17 for the other walls.

(You can’t mix runs on the same wall, because different runs, printed at different times with different batches of ink, will be slightly different shades. This very slight color difference will show up on the wall as a striped or “paneled” effect.)

The wallpaper is by York. It is a non-woven material, comprised of synthetic fibers rather than wood and cotton. The synthetic material does not expand when wet with paste, which means the wallpaper can be hung via the paste-the-wall method, with no “booking” or “soaking” wait time needed.

Interestingly enough, Run 16 behaved differently from Run 17. I hung the accent wall with Run 16 quite successfully using the paste-the-wall method.

But when I started the next wall using Run 17, bubbles and wrinkles developed. The paper was absorbing moisture from the paste and expanding on the wall, creating the small bubbles. Quite unexpected with a non-woven material.

The solution was to paste the back of the wallpaper, rather than the wall. This allows the material to absorb moisture and expand a tad before you get it to the wall, so it will behave itself once it is on that wall.

Unlike a traditional paper, this non-woven material did not need a lot of time to absorb moisture, but could be pasted and hung immediately. This greatly speeds up the installation process.

Pasting the paper has an additional advantage in that it renders the material more supple and pliable, which makes it much easier to work around corners or manipulate into position in tricky areas.

Shading, Irregular Strings, Bubbles – Disappointments in Walquest Faux Grasscloth

April 18, 2021
Look dead-center – the strip on the right is slightly darker than the strip on the left (Effect shows up better in person than in photos). We call this shading, or paneling. Even though the pattern can be matched from strip to strip, which eliminates the eye-jarring break in the design at every seam which you get with real grasscloth, I am disappointed that Walquest allows this color difference. I’ve noticed it on each of their colorways. It is less noticeable on this light version, but is readily apparent in their darker colorways.
At the right edge of a strip of faux grasscloth wallpaper (center in the photo), a string either didn’t get put in place, or was pushed too far to the side. Either way, when this strip on the left is butted up against the next strip to the right , this “missing string” creates a very obvious void area, which runs vertically for about 4.’

I have long loved this Walquest alternative to grasscloth, because it has the texture that clients are seeking these days. But it sidesteps many of the problems with real grasscloth. Because it has a pattern that can be matched from seam-to-seam, so you don’t get the visible breaks in the reeds at every seam as with real grasscloth. And because it’s man-made, so the color is more uniform, reducing the color differences between strips that is prevalent with real grasscloth. (Do a Search here (upper right corner) to learn more.)

Unfortunately, I am becoming disenchanted with this product. The last several times I’ve worked with it, there have been color differences (shading / paneling) between strips. And a couple of times, I’ve had issues with strings not being uniformly placed across the strips.

Fixing Weird Things That Happen To Wallpaper

December 6, 2020

The top photo shows a stain on the wallpaper that is probably related to a rain or hurricane event a few years ago.

Water stains (and also other substances, like rust, blood, ink, oil, tobacco, tar, cosmetics, and more) will bleed through wallpaper. So, before patching the area, it is imperative to use a stain blocker to seal the problem. My favorite is KILZ Original oil-based.

KILZ will seal off the stain all right. But wallpaper won’t stick to it. So, in the third photo, you see where I have primed over the KILZ with a wallpaper primer (tinted light blue, for visibility). It’s not necessary to prime the entire wall area to be patched, because this type of wallpaper will stick to itself with just plain old adhesive.

The striped pattern made for an easy repair. I took a straightedge and sharp razor blade and trimmed along the striped design, creating a long skinny patch. See fourth photo. You can also see the strip pasted and booked (folded pasted-side-to-pasted-side).

Once that sat and relaxed for a few minutes, I took it to the wall and appliquéd it over the damaged area, going the full height.

There was a very slight color difference between the paper that had been on the wall for 20 years and the paper that had been in a dark closet. Had I placed the white area of the patch next to the white area on the existing paper on the wall, the color difference would have been noticeable. But trimming along the blue stripe gave the eye a logical stopping point, and so the color difference is not detectable.

In the finished photo, you would never guess there had been anything amiss with this wall.

I used this same technique to patch over the bug-bite holes in yesterday’s post.

And another good reminder that it’s always best to order a little extra wallpaper, in case of the need for repairs later. Store the paper in a climate-controlled space … not the garage or attic.

The wallpaper is by Schumacher, and appeared to be an old-school pulp paper material.

Same Run? Different Color?

July 18, 2019


Top photo. Look carefully. You are looking at the start of a printing run on two separate bolts of paper. On the bolt to the left, the color looks pretty uniform.

But on the bolt to the right, you can see a horizontal line where the background has been colored. It’s faint, so look closely. In addition, you can definitely see that the paper on the right is darker than the paper on the left.

If there were more fish present, you would also see that on the right, the greys are a little darker and the reds are a little stronger. There are also more brown speckles in the background of the grasscloth on the right.

What happened was, too little paper was ordered (a simple mix-up between rolls and yards), and so more had to be ordered, and then custom-printed.

The interior designer stressed to the manufacturer that the new paper had to be the same run number (all bolts printed at the same time out of the same batch of ink). The manufacturer’s reply was that their precision printing and ink-mixing was such that there would be virtually no difference in color between what we had already, and what they would print fresh and send to us.

As you can see, that is not the case. Although these differences are minor, if strips from these two bolts were placed next to one another on the wall, the color difference would be pretty noticeable.

So, accommodating for this color difference, we lost about three yards of (expensive) wallpaper.

Run Numbers Are Important

April 14, 2019


I hung two wallpapers today, both from Anthropologie, and in both cases, the homeowner measured and purchased paper before I had measured and figured how much to buy. In both cases, they were a double roll short. I told them that when they ordered the extra double roll, to be sure to ask for the same run number as the rolls they already had.

Unfortunately, in both instances, Anthropologie sent a different run. Probably, the guy in the warehouse didn’t get the message from the people in the order department, so he just pulled any old bolt of paper off the shelf.

Run numbers DO make a difference. As you can see in the second photo, the butterflies are clearly different colors. And in the third photo, the color difference (red flower, brown leaf) is less dramatic, but still noticeable. The white background is probably a slightly different color, too. If these strips were placed next to each other on the same wall, you would notice an abrupt color difference the full height of the wall.

So it’s important to make sure that all your bolts of wallpaper are of the same run number.

Run number, also called batch number or dye lot, refers to rolls that were all printed at the same time. The next time the manufacturer is ready to print up that pattern, he will mix up a new batch of ink – but that batch might be a slightly different shade than what was printed previously.

Because these color differences will be noticeable on the wall, it’s important that they not be used next to each other. You can use different runs on separate walls, but not on the same wall. If you are forced to use broken runs, as they are called, you’ll need to buy a little extra paper, because there will be more waste as you switch from one run to the other.

Different Runs

February 8, 2019


Look at the center of the photo. See that slight color difference between the strip on the left and the strip on the right? This is most likely due to the two strips coming from two different run numbers. These can also be called batch numbers or dye lots.

This means that all paper that is printed from one batch of ink is given a run number. Three months later, when the manufacturer is ready to print another lot of wallpaper, a new pot of ink is mixed up. Chances are that that new kettle of ink won’t be exactly-dactly the very same shade as what was used previously.

This means that the two batches of wallpaper will be ever so slightly different in color. If strips of paper from the two different runs are put on the wall next to each other, you will notice the color difference. So each batch of ink, and the paper that is printed with it, is given a run number.

That way, the installer can be sure that all the wallpaper for his job will be printed at the same time, of the same run number, and all the same shade.

Checking for run number is the first thing every installer should do, before starting to hang wallpaper. In fact, in my “how to prepare for install day” info pack, I ask my clients to check to be sure all bolts are of the same run number. That way, if there is a problem, there will be time to return the bolts and get new paper that is all of the same dye lot.

If you end up with a broken run (two or more different run numbers), it is possible to use the paper, but you have to keep the different runs on separate walls… your eye will not notice a subtle color difference if the papers are on different walls. But this uses up a lot more paper.

Stretching the Paper to Avoid a Pattern Mismatch / Color Shading in Grasscloth

October 28, 2018


Two things about this photo. First, you can easily see the color difference between the narrow panel on the left, and the one to its right. You can also see that the color of the grasscloth darkens 2/3 of the way down the middle strip.

This variation in color is normal – even expected – in grasscloth, and is called “shading,” or “paneling.” It’s referred to as the “inherent beauty of this natural product.” But, personally, I don’t care for it.

Read my informative page to the right, to learn more about grasscloth.

Another thing to note … this corner is the last corner in the room to be papered. Virtually always, this last corner ends in a pattern mis-match – which can jar the eyes. So I placed it up over the door, in the least conspicuous space I could find.

Indeed, since the distance between the motif on the final strip did not sync with that on the first strip, the pattern was going to end up with a floral stem being split in the corner, leaving half of the greenery visible and half cut off. I didn’t want any cut off flower stems.

So I “grew” the paper. The distance between the flowers was supposed to be 5″. I used some scraps of paper to cut a strip 3.5″ wide, and another 4″ wide. This gave me an expansion of 7.5″ – wide enough to bridge the final distance without cutting off any flowers, but not wide enough for the eye to detect that the spacing was not exactly as the artist originally plotted.

The pattern is “Acanthus” and the manufacturer is Schumacher.

Slight Color Difference

June 4, 2018


Look closely, just to the left of center, and you will see that the strip on the left is slightly darker than the strip on the right. This is called shading, and is because, in this case, the left side of the wallpaper is a slightly darker color than the right side. Therefore, when two strips of paper are butted against each other, the difference in color can be seen.

In this powder / laundry room, with poor lighting and a busy pattern and a relatively mild case of shading, I didn’t consider it bad enough to halt the job and reorder more paper, and so I went ahead and hung the room.

Everyone loves the finished room.

I am probably the only one who can spot this minor color difference.

Run Numbers Running Wild – Not Acceptable

April 4, 2018


For this job, the vendor sent FOUR different run numbers, plus two bolts that had no run numbers at all. It all had to be sent back and exchanged for new paper – all in the same run, please!

Run numbers are very important. When wallpaper is printed, each batch is marked with a run number. The next time the manufacturer makes a batch of wallpaper, a new vat of ink will be mixed up, and it will be an ever-so-slightly different shade from that which was used before. So that new batch of wallpaper will be given a new run number.

These color differences are minor – but if they are placed next to each other on a wall, you will have a very noticeable color change from one strip to the next. In the second photo, you can probably see the difference in color between the red flowers, and maybe even the green and brown foliage.

In the third photo, a smaller rectangle of the wallpaper pattern has been placed on top of a larger rectangle. All around the perimeter, you can see a slight color difference between the reds, greens, nad browns.

But it’s important to realize that the background will also be of a slightly different shade.

When two strips of two different runs are placed next to one another on a wall, the shade difference will be obvious in the form of a floor-to-ceiling slight-but-noticeable color difference. https://wallpaperlady.wordpress.com/2016/07/19/two-runs-are-not-fun/

It’s possible to work with this, by “breaking” the runs in a corner. But this uses up a lot more paper, and it’s too complicated to explain here.

This wallpaper was bought from an on-line mass-marketer. I like the quality of their products. But they seem to have no clue of how wallpaper works, and the customer service person had no grasp of what a run number was or why it mattered. From a vendor like this, you can pretty much expect that they have a bunch of stock shoved into shelves in the warehouse, and when someone buys some, a worker just goes out and pulls any old rolls from the stack, willy-nilly, with no regard to run number, damaged goods, and may not even check to ensure they are all the same product number – A coupla months ago, I got the same pattern but in two different colorways.

The bottom line is, buy your paper from a reputable source that specializes in wallpaper, check the run numbers when the paper arrives, and, if necessary, keep separate runs on separate walls.

Color Difference Due To Fading Over The Years

January 24, 2018


I hung this original paper more than 15 years ago. Some areas had become stained, so I was called to fix it. Luckily, the homeowner had saved the left over paper, so there was enough to replace the damaged strips.

You can see a slight difference in color between the strip on the left, which was hung 15 years ago and has been exposed to light all that time, and the strip on the right, which has been stored in a dark closet until I put it up today.