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How To Measure Your Cover

We understand and appreciate that this is a nervous point for many people. “How do I measure my hot tub? I have no idea where to begin!” Well, we are here to help.

Please rest assured that we will do our best to insure that every cover is the correct and best size before production. So, to that end, we have written some very, VERY in-depth directions on how to measure your hot tub. These are probably way to in-depth for most people, and we get that, but we are here to help.

You will not find more in-depth or precise directions on how to measure your hot tub for a new cover anywhere else on the internet. This is how serious we are at making sure you get what you want.

Otherwise, please just drop us a call, text or email and we’ll help.

But first! We do have a very extensive database of hot tubs sizes and shapes. So, if you know the make, model and year that your spa was made, chances are we already have the information we need to make the perfect cover for you. Drop us a line and give us this information and we’ll reply with a recommended size ASAP.

Advanced Spa Covers – Hot Tub Cover Measuring Guide

Please open this page from your cell phone or tablet for quick reference by your spa, or print it if you prefer and bring it with you to the spa and lets dive in. (pun intended)

1)      Do you measure your old cover or the spa itself?

Measuring your existing cover can be the quickest and easiest option, but first we need to make sure that is the best choice. Before measuring your old cover, please review these questions:

  1. Your old cover must be in reasonable condition. Natural wear and tear is fine.
  2. Make sure your old cover has not warped, become water-logged, or changed shape or size.
  3. And most importantly, make sure you are happy with the way your old cover fits!

If all 3 questions above are favorable, then provide us the dimensions of your old cover, it is the easiest and quickest way most times.

If not, then measure your hot tub if any of these conditions exist:

  1. You have no existing cover.
  2. Your current cover is warped, has become waterlogged, or changed shape or size since its purchase.
  3. Or, if you are unhappy with the way your current cover fits in any way shape or form.

2)      Key points to consider while measuring:

Round up measurements to nearest half inch or inch. For example, if you measure 84 ¼”, write down 85”, if you see 92 ½”, write down 93”

A cover that is 1-2 inches too large fits nicely, is easier to open and close, and odds are that extra inch or two will not affect your price. If it does, we will notify you before production begins to give you the opportunity to make adjustments.

The biggest concern with a cover that is too small, the skirting may be too tight.

If your measurements are close to being square, it probably is a square. For example, if you measure your spa at 84 ½” x 85”, your cover is actually 85” x 85”. Spas can warp and change shape over time.

3)      Where to Measure

a) If measuring your old cover:

If after reviewing Section 1 above you elect to measure your old cover, simply lay the tape measure across the top of the cover and measure from flat edge to flat edge in both directions and also provide the corner radius. We need these three dimensions only.

b) If measuring the spa itself:

There are many spa styles and each style should be measured differently.

Here are diagrams of the 3 most popular styles showing where to measure the width and length for the best possible fit of your new cover:

4)      Choose a Shape and Measure:

Enter your measurements here: A_________ B_________ C_________ D_________ R_________ .

Use only the designated dimension needed for your shape. For example, the square only needs two numbers, A and B, while the square with rounded corners needs 3 numbers, A, B and R for the radius.

Round up to the nearest half or full inch as noted in Section 2 above. “R” stands for radius. Enter any notes, questions or concerns you may have here: ____________________________________________

If you are placing your order via our website shopping cart, we provide a box located near the “Check Out” button to enter these numbers. Simply enter them as shown here “A = , B =, C= , R= , etc. And feel free to add any other notes you feel important in the same box or via email.

5) Select What Direction the Hinge Goes:

There are two basic hinge directions. The hinge can fold the A dimension in half, or the B dimension in half as shown. More to come on that, but first…

The hinge on your new cover does not necessarily have to go the same direction as your old cover does. Things to consider when selecting the hinge direction are:

  1. Which side would you prefer to enter/exit the spa from?
  2. Where are the controls located? You want easy access to these when the cover is open.
  3. Are you going to use a lift and if so, what style of lift?
  4. Are their obstructions such as a wall, fence, or post in the way?
  5. An open cover can provide privacy as well. Do you want it opening on one side or another for added privacy?

Other key points to consider include:

Is your cover square or symmetrical? In other words, does it measure the same dimensions in all directions? If so, the hinge direction for production purposes does not matter since you can simply rotate the cover on site to the angle and direction you prefer since it measures the same in both ways.

If we see anything unusual about your order, rest assured that our team will always reach out to you with any questions before production begins to help ensure we have it right.

A Fold or B Fold:

An “A Fold” cuts the A dimension in half, a “B Fold” cuts the B dimension in half as shown in this diagram below:

Circle Your Fold Choice Here: A Fold   B Fold

6)      The Corner Radius

The corner radius is an important measurement. If measured wrong, your skirting may be to tight making the cover hard to open and close. You may consider specifying a smaller radius to allow a little extra room for ease of opening and closing your cover. Contrary to what seems like common sense, a smaller radius will actually give you more room. Due to the change in the curve, a smaller radius will extend the corner of the cover out further from the corner of the hot tub giving a looser fit of the skirting.

Using a carpenter’s square:

Using a carpenter’s square is the quickest, easiest, and most accurate way to measure a corner radius. Simply hold the square up tight against the corner as shown below making sure that both straight edges of the square align parallel with the side walls of your spa lip. The radius is then found where the acrylic meets the square.

To get the best fit, in the case of the corner radius we recommend to always to round down to the nearest inch. If your square shows a corner radius of 6”, round this down to 5” for the best fit.

Measuring the Corner Radius Without a Carpenter’s Square:

Use yardsticks, rulers, cardboard, sticks, or anything with a straight edge and hold them in alignment with the edges of the spa as shown.

Measure the distance for the radius with ruler or tape measure as shown.

Enter Your Radius Measurement Here: _______________________________________________

6)      Measuring the Skirt and Strap

The leading purpose of the skirting is to protect the acrylic lip of your spa from sun damage. Contrary to popular belief, it is not there to save energy because by the time the heat gets out that far, it is already gone. Plus, all ASC covers are fully gasketed around the entire perimeter preventing that heat from getting past the lip anyways. The skirting can also add a very nice finishing look to the cover.

ASC offers custom skirt lengths. We also offer custom skirt colors and fabrics too! Imagine a cover carved with Koi Fish with skirting that had Koi Fish swimming around the spa for example. Fun!

To measure the skirt of your spa measure from the bottom of the cover down to the bottom edge of the skirt.

A 4” standard skirt length will be used if no custom length is requested.

Enter Your Covers Skirt Length Here: _______________________________________________

Safety Strap Length:

To get an accurate measurement of the safety strap, you need to measure it from the bottom of the cover down and include the skirt length. Due to production variations it cannot be guaranteed you will receive a matching strap placement, but new buckles will be supplied. Straps are required on every cover to be ASTM compliant.

A 6” standard strap length will be used if no custom length is requested.

Enter Your Safety Strap Length Here: _______________________________________________

Special Circumstances:

Does your spa have any of these special circumstances?

  1. Pop Up Speakers
  2. Raised Speakers
  3. Vertically Arched Walls
  4. Infinity Edge
  5. Sloping Edge
  6. Any feature, knob, control, waterfall, etc., that protrudes above the lip of the spa

If so, please make note of that here: _________________________________________________

Additionally, Advanced Spa Covers is the only mass cover manufacturer available that can custom make covers that include custom gasketing, removable skirting, and odd things like waterfall cut-outs and passageways. We can even do raised speakers, arched walls and infinity edges.

In closing, take good notes and remember, “a picture is worth a thousand words”. We will gladly take your photos to help you design he best cover, with the best fit and function possible.

Drop us a line today and we’ll work together.

Thank you,

The Advanced Spa Cover Team