Why is it that some Hot Tub manufacturers inject their Hot Tubs  with full foam? Ask them as it could be and is often simply hiding a cheaper form of construction. So simply ask the sales representative why is it that they inject their Hot Tubs with full foam? If they come out with the old Chestnut that all the pipes are  covered so as  to keep the noise down it does make wonder what they mean, indeed  have you ever heard such a stupid statement - what noise – it must be a very poorly engineered and designed spa  if that is what they have to do – the plain truth is that they start with the cheapest way to make a spa as they don’t use a quality branded acrylic like Lucite ™ and then you ask yourself the simple question as to why they do not – it is very simple – Lucite ™ costs some four times as much as what they use. In my view based on many years experience the worlds leading Hot Tubs are made using proper branded acrylic such as Lucite ™  if it does not have a shell  made out of a sheet of either Lucite or an equivalent such as Arisitech Quarite ™ then I think you need to question how well the spa is made internally. It may be cleverly packaged but just because the wrapping paper is good does it mean that the contents of the box of chocolates’ are any good. When they say it is filled with foam that means that you can not see where the pipes go if there is a leak and it could well be that there is  some inherent weakness in the shell in that it needs the foam for extra strength in any event in my view it is an out of date manufacturing process.   One large maker of Spas has made a practice of selling cheap-to-make spas in an expensive presentation package, but the end user does need to know that they are made with an inferior shell material. This company fully foams their spas as structural support for the thinner and porous shell material (thus creating a service nightmare if there ever should be a leak somewhere). They also openly vent their cabinets which may lead to bug and rodent infestation that can hide and nestle inside the blown in insulation, and also by venting the cabinets they are loosing expensive heat.   Next time you are thinking of  buying a Hot Tub Jacuzzi I suggest that you probe a little beneath the wrapping and  presentation and don’t accept what is clearly the glib patter of  a salesman who repeats by rote but is not that of someone who has a passion for their products.