insulating pex pipes with foam tubes seems to have done nothing

I just moved into a new home which was plumbed with pex piping (is pex referred to as piping or tubes??). The full basement is fairly cold, maybe 50-60 degrees and the pex lines were not insulated. Needless to say the water in hot pipe lines did not stay hot for very long. I wrapped the pex lines (about 70-80 feet) with foam insulation and did my best not to make any holes wherever possible. I did need to make small notches where the pex was attached to the floor joists but made the notches very tight to the floor joists. I used the hot water around 10pm on the previous night and in the morning around 8am tested the water and it was ice cold again. Am I expecting too much from the insulation I put on? I understand that the heat in the pipes will dissipate over time, but how long will it last? What other options do I have?

Thanks,
Steve

 

What you are seeing is completely normal. Even with the insulation, the water might stay just warm for an hour or so...but not hot.

If you really want immediate hot water...you'd need to install a small point of use heater or a recirculating system. Neither of which is cheap or real simple to do. They do make systems that can be plumbed in to a kitchen or bath faucet. Simpler to install, but still a bit pricy I believe. They will also raise your costs for heating water somewhat.

 

Steve, welcome to the forums, BTW. Do an experiment. Put hot water in an insulated mug with a lid. How long does it stay warm in the basement? Same theory. Nothing to keep it circulated with the hot water supply and it will go cold eventually, especially overnight. A better location for the water heater would have been midspan under all the applicances/bathrooms/kitchen. Shorter run, hotter water, quicker.

 

>>> Am I expecting too much from the insulation I put on?

 

All good points - thanks for the feedback. I wanted to use the fiberglass insulation, but there's just no room for it anywhere. The pex is either butted up directly against the bottom of the floor joists every 16 inches or attached along side a floor joist when running parallel. I'm thinking the point of service heater for one of the sinks might be a good option. The only problem with that is that it only services one hot water outlet.