How to Measure Your Hot Tub for a New Cover
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Is it time for a new hot tub cover and you are worried about getting a perfect fit? We have setup this step by step guide to help you measure properly. Even if your hot tub manufacturer claims they have your specific hot tub cover measurement on file, be sure to double check all measurements before you commit to spending your hard earned money on a new one.
Step 1 – Measure the Outside Dimensions
Let’s start with the easy measurements first. Start with the width and length of your tub. You want to measure both the same way. Measure the outside dimensions of the acrylic portion of your tub from the outside lip to outside lip on the opposite side.
When taking length and width measurements you may add up to 1/2″ on both the length and width. This will give you a 1/2″ of play around your spa cover.
Step 2 – Measure the Skirt
The second measurement is for the skirt, which is the flap that hangs down around the edge of the cover. There are two possible scenarios for doing this:
The first option is if you have a ledge under the acrylic. You want to measure from the highest point of your acrylic to top of the ledge below. Make sure you don’t go long on this measurement. It’s better to be a little bit short or the skirt will bunch up and the cover will not seal.
The second option, if you don’t have a ledge, is to measure from the highest point of your acrylic to the bottom of the lip and then simply add a half inch.

Step 3 – Measure the Corner Radius
If your hot tub has round corners, this third measurement is to figure out the radius of corners. The simplest way to measure is with a carpenter square. Again, you want to measure on the outside edge of the acrylic. Put your square on the outside of the acrylic. Now measure from the inside corner of your square to where the acrylic stops bending. This is the radius of the corner.
It is better to be a bit smaller on this measurement then being long. Make sure you check each corner to make sure they are all the same. If this measurement is too long it will not cover the corners of your hot tub. This is the opposite of what most people think.

Step 4 – Check the Fold Placement
Make sure you request the fold on your tub if it is longer on one side then the other. The fold won’t matter on a square or round cover. In almost every case, the cover will be divided in half and fold on the longest side.

Step 5 – Measure the Strap Length
This is something you need to measure if you have buckles for straps. Start from the bottom of the skirt to the end of the buckle to get this measurement. If you need specific strap locations, measure from the center of where they are to be placed.
Does Your Hot Tub Have 1 or More Cut Corners?
To measure a hot tub with 1 or more cut corners, first measure the width and length from the outside lip of the acrylic to the opposite outside lip. The second measurement is to measure the cut corners. In most cases they’ll all be the same. Measure from point to point. If the corners aren’t the same, then you will have to follow the instructions for special shapes below.
In some cases the cut off corners will be rounded. The easiest way to measure this is by using masking tape or 3 straight edges. Arrange the tape on the outside of the acrylic. Where the tape intersects (on the inside corners) is where you want to measure from. It’s better to measure this one a bit short, than long. If it is too long it will not cover the corners of your tub. This is the opposite of what most people think.
Is Your Hot Tub an Octagon?
If your hot tub is an octagon shape, make sure each side is the same length, if not your tub is not a true octagon and you will have to use the special shapes section below.
The first measurement is to measure from the outside lip of the acrylic to the opposite outside lip. The next measurement is to measure the length of one of the sides on the outside of the acrylic from point to point. The final step is to measure the skirt length the same way.
Is Your Hot Tub Round?
If you have a round hot tub, then simply measure the longest distance from the outside lip of the acrylic to the opposite outside lip. Then measure the skirt length the same way. Remember to add 1/2″ of play.

Is Your Hot Tub a Special Shape or Requires Cut Outs?
Many tubs are not perfectly symmetrical and require special measuring, such as an ellipse, non uniform octagon, or a custom shape. Some include obstacles that will not allow the cover to sit evenly on the edge of the acrylic, such as speakers, waterfalls and control panels. These tubs will require you to draw up and send in a template to allow the cover manufacturer to account for these modifications.
Bottom Line
Measuring your hot tub cover is as simple as getting out a tape measure and first noting the length, then the width of the existing spa cover. We hope these easy to follow instructions will guarantee that your new replacement hot tub spa cover will be the perfect fit.