bl092699

By Paivi Suomi on September 26, 1999

How to Calculate Yarn for Warp

ORIGINAL FILE DATE: 09-26-99
DUE TO A WEBSITE CRASH THIS PAGE IS UNDER RE-CONSTRUCTION. PLEASE BE PATIENT WHILE I UPDATE THIS PAGE.

THANK YOU – Päivi

Even if you have a pre-determined pattern, it is a good idea to double check that you have
sufficient yarn to complete your project.
warp board

Take-up & Shrinkage

To calculate the length of warp required, take the length of your finished project and add 10%
– 15% for take-up and shrinkage.

e.g. Finished project: Table Runner length = 36″ + 2 inch hems = 40″
Take up & shrinkage 15% = 6″
Total length = 46″

Loom Waste

You will need additional warp length to be able to tie the warp ends to the back and front of
the loom. This is called “loom waste“. Loom waste is generally about 27” but I add a
full yard for loom waste. This gives me a few additional inches of warp for sampling and
playing with new designs or colors.

So, for this project you would need:
46″ + loom waste 36″ = Total 82″ or 2.3 yards warp length.

Make More

Because there is always a considerable amount of loom waste in a weaving project, it is
usually advisable to make more than 1 item at a time.
To make 2 table runners, the warp length would be:
2 x 46″ = 92″ + loom waste 36″ = 128″ or 3.5 yards.

Width of Project

Next, you will need to know the desired width of your project. Add 10% – 15% for take-up and
shrinkage.

Project width: 17″

Takeup & shrinkage – 15%: 2.5″

Total width: 19.5″

EPI

You will now need to calculate how many ends of yarn you require. Using the sett that you
figured out above, multiply the sett (number of ends per inch) times the total width of the
project.

Sett: 20 epi
Total width: 19.5″

18 x 19.5″ = 390 ends

Total Warp

Each warp end will be 3.5 yards long and you will need 390 ends. To calculate the total warp
length, multiply the total warp length x the total number of ends.
warp length: 3.5 yards

# ends: 390

3.5 x 390 = 1365 yards

YPP

Yarn is usually sold by weight, in number of lbs. or grams. The yardage measurement is
sometimes shown on the cone of yarn, or you can ask your yarn supplier how many yards per
pound there are in the yarn you purchased. The hemp yarn shown above has 1500 yards per pound
(ypp). So you would need 1365/1500 = .9 lb. of yarn for the warp.

Weft

Don’t forget that you will need yarn to weave the weft as well. If you are using the same yarn
for weft as well, you will need approx. the same amount to complete the two table runners –
1.8 lbs.

Part 5: Warping Board