pond liners

The choice of pond lining is of critical importance. This is definitely not the place to skimp - whatever your choice, make sure it has some longevity. Factors to consider when choosing a membrane include durability, ease of installation, design capability, climate and value for the dollar. We recommend 45 mil EPDM liners which are tough, easy to install and can handle the freeze/thaw cycle that temperate climates present

We often replace PVC liners, which generally start leaking just as the pond landscaping starts to mature and look great

flexible pond liner options

E.P.D.M., P.V.C., Butyl Rubber and Permalon
E.P.D.M. is a rubber compound and comes in a standard thickness of 45 mil. 1 mil = 1/1000th of an inch so 45 mil liner is 1.1 mm thick equivalent to about 10 sheets of paper. It is tough, durable, readily patchable and has good elasticity. [E.P.D.M is also available in a very tough 60 mil thickness]. P.V.C. membranes come in thinner widths and have a shorter life span of approximately 10 years due to its vinyl construction. It becomes brittle over time and easily develops holes which of course leak. My advice is not to even consider P.V.C. for your pond, its day has come and gone

I have worked with Butyl rubber just once and frankly was not overly impressed. Although it purports a 50 year life span, I found it very prone to punctures. Strangely it can be ripped easily with minimal force which was not encouraging. Butyl is lighter than E.P.D.M. however and has a canvas like texture. The pond I used it with is still holding water

Permalon is a product that I have no experience with. It is apparently light weight so easier to move around but I have read that it is stiff, of plastic construction, prone to puncture and difficult to patch. The bottom line is, for a natural and durable looking pond, EPDM is still the premier and proven choice
  • Butly rubber is purported to last 50 years
  • Comparing 4 and 10 oz geosynthetic
  • Liners weigh about 1lb. per 3 sq. feet. Rock carts helps
  • This cheap PVC liner is better off replacing

A bad choice - too shallow, hard to install and poor durability

plastic shell ponds

Many hobbyists get their start with types of ponds. Unfortunately they have no redeeming value. They are overpriced for the volume they provide, easily punctured and difficult to install because they need to be supported properly

The other huge disadvantage is they are too shallow to keep fish in successfully. If the raccoons don't kill them, the fluctuating temperatures and Winters fury will
Concrete ponds offer straight walls but are expensive to install

Concrete Ponds

As for concrete, gunite and block and render ponds, I have limited experience in building them. That being said, my very first pond was concrete. We have also applied liquid rubber to stop concrete ponds from leaking on many occasions. It is my feeling the effort and cost are not justified with concrete ponds. However, in the case of very sandy soils and a desire to have vertical pond walls, concrete and block or gunite etc. are necessary. If built properly and cost is no option, a concrete pond rendered with fibreglass will last a lifetime - likely without issue

A major disadvantage with rigid ponds aside from the cost is the fact that the finished look is not a natural one. The pond takes the appearance of a a swimming pool with fish in - something I find unattractive

spray on Pond liners

We did try to make 2 ponds using liquid rubber, sprayed on application using the and instant set. We found in both cases they leaked, and we had to revert to epdm liners. We have had good success with the paint on liquid rubber, which we sell, and created a 6 x 6 wooden tank shown here

I think other products like polyurea are superior, but are harder to apply than made out to be and are very costly. At this juncture, we still prefer epdm liners. Of course, your mileage may vary

Taping Folds

To avoid dead spots and create an appealing finished look, liner folds should be taped down After the bottom drain is sealed, start filling the pond and pull out all the wrinkles. You will not eliminate all of them, but can make a huge difference. The folds need to be worked into place as they tend to bunch up in the corners. V type folds tend to work best, as the name implies it is a fold increasing in size from bottom to top in an expanding taper

As the pond continues to fill, work your way around the perimeter taping tight folds into place. You do not want to tape too high above the water level - 2 feet at most. If you do, you will likely find the taped folds are too loose or conversely to tight

Although it is tedious and costs a little more, liner taping should be considered essential and if not undertaken, functionality and aesthetics will suffer

more tips on how to tape liner folds
  • Without taping, some large folds can appear
  • Taping the folds creates a nice neat finish
  • Liner ponds will like very natural if installed properly and not powerwashed