Assess traffic wear on rug. Is there a pattern of wear through the middle? on one corner? Does the pile height vary greatly? Hopefully, your rug is worn evenly without significant variance!
If your rug shows the slightest bit of foundation (worn past knot heads) use the "Very Low and/or Very Uneven: foundation may show" selection. If your rug shows a lot of foundation, use the "Very Low and/or Very Uneven: foundation showing" selection.
For purposes of the rug estimator pro, use the following guidelines to assess your pile height
Normal/Original Height: Pile shows absolutely no signs of wear. The pile is the same height as it was originally. The pile is crisp and clean (no "blooming") showing no matted areas. Under close inspection, the pile appears to have never been walked on.
Low than Normal but Even: The carpet shows minimal and very evenly distributed wear. If rug is perfect in every other aspect, a rug with low and even wear can still be in "Good" condition, but not excellent. If the tips of the wool are "blooming" with no other wear issues, this selection is probably appropriate.
Low and Uneven: Carpet shows moderate signs of traffic such as a lower pile toward the edges of the rug or foot patterns around where a piece of furniture may have been placed. A rug with low and uneven wear at best is in "Good" condition.
Very Low but Even: The pile shows allover wear. This could mean the pile is worn down to the "knot heads" however, in this category, the rug shows no foundation whatsoever. If rug is perfect in every other aspect, a rug with very low and even wear can still be in "Good" condition as the very highest category as long as is no evidence of other imperfections. With any other imperfections, the rug may be more appropriately claimed in the "Fair" condition category.
Very Low and/or Very Uneven: foundation may show: The carpet is worn heavily in spot areas. For the most part, the lowest part of the pile will show "knot heads" and may also expose the rug's foundation in small areas. Use the repair tab to detail the percentage of foundation showing across the rug. At best, a rug with very low and uneven wear will have only one small area worn to the foundation, and its highest category would be "Fair" condition. If foundation shows across more than 5-10% of the rug, it must be placed in the "Poor" condition category.
Very Low and/or Very Uneven: foundation showing: This category indicates a rug that was not rotated to distribute wear. Traffic patterns are obvious as the pile readily shows where a coffee table or large piece of furniture may have been placed. This rug will show areas which are close to the normal or original pile height in some areas, and others which show knot heads and maybe even some foundation. A rug with very high and very low areas at best is in "poor condition"
New with Uneven Shearing: Unrelated to wear. This category is intended for a brand new carpets with high and low spots from uneven shearing. If your carpet has a very crisp pile, with lines or valleys cut into the pile (which does not follow patterns or designs) the shearing may have been poorly finished. Take a look at the example on the bottom of this page.
Both photographs below show the front of an antique (100+ years of age) Persian tabriz. The section shown below is an accurate representation of the wear across the carpet. The wear is "Very Low but Even." The rug shows no foundation, and wear does not go further than the carpet's "knot heads". This rug has no repairs, no color run and no exposed foundation. It can be considered in "Good" condition with "Very Low but Even" pile height.
Although it appears as though the above and below photographs could be the reverse side, they are actually photos of the face of the rug (the lower image is under magnification.) A carpet in this condition has life left in it. However, use in a high traffic area would not be advisable.
Photographed below is the face of a semi-antique Persian "American" Sarouk. The green arrows point to areas of hard and heavy wear. In some places, wear has only gone down to the knot heads. The second arrow from the left shows a slight exposure of foundation. For this particular carpet, there is a fair amount of pile left throughout the rest of the rug. For purposes of the rug estimator Pro, select "Very Low and/or Very Uneven: foundation may show."
Above is an old Afshar rug (mid 1920's) which shows signs of oxidation and wear. Most of this wear results from use. The natural dyes used in production have also degraded the wool fibers causing them to be brittle and more susceptible to breakage. A rug eventually wears down to the foundation. Deteriorating fibers accelerate the process. This is more easily observed in person. In this image above, you can see the pinkish red is lower than the blue and browns because certain colors of [natural] dyes are more aggressive in the aging process. Therefore, it is not unusual in older rugs to have an embossed appearance caused by certain colors maintaining a varying average height than others. This is primarily due to the different degradation of fibers, dependent upon the harshness of the original dyeing process. For purposes of the Rug Estimator Pro, evaluate the carpet as you would any other.
So your rug looks great from 10 feet away... How about up close?
This section is dedicated to those rugs which do not make it into the excellent category.
Take a look at the two carpets as photographed below. They are the same colors (slightly different dye lots) same size, and same pattern. Should they be evaluated on the Rug Estimator Pro as having the same pile height or being in the same condition?
Closer inspection of these two rugs, side-by-side, shows significant differences in the pile detail. The rug on the left is a brand new rug, showing no wear whatsoever. The rug on the right shows both a slight loss in detail, and a lower than normal pile height. The yarn has opened up from traffic and has become less defined: this is known as "blooming."
The image below shows the same rugs rolled to accentuate the differences in the pile. Note the carpet on the left shows individual fibers which are crisp, clean and evenly sheared. The carpet on the right shows the used rug in a similar area with somewhat uneven pile height, a slightly "matted" look, with significantly less detail.
For purposes of the Rug Estimator Tool, the carpet on the left, with all other factors being perfect, can be noted as belonging in the category of "Excellent" condition with "Normal/Original Height". The rug as shown on the right, however, should be noted as being in "Good" Condition at best, with "Lower than Normal but Even" pile height.
The photograph above shows a prime example of an unused rug with uneven shearing. Notice the blue line which follows the actual shearing pattern of this particular piece. For purposes of the Rug Estimator Pro, document this rug as "New with Uneven Shearing."