DIY repair of rotted frame?

[Red MC]

We currently have a 2004 Artesian Emerald with rotted bottom frame members and a carpenter ant infestation.  I'm trying to figure out if I should I attempt repair.  I wouldn't even ask if not for the COVID-19 supply & demand problem, which means we can't get a replacement here until November or (more likely) later in the winter.

Some details:

The spa does not have a sealed bottom, and the bottom skirting below the side panels is made of treated lumber.  It's on a stamped concrete patio, so I placed it on a 0.5" layer of neoprene gym mat which effectively sealed off entry by insects.  That worked for a long time, but we live in Southern NH and the bottom skirting is exposed to snow and ice.  It is shaded by a privacy fence and one half gets no direct sunlight for ~6 mo/year, so any moisture takes forever to dry.   Eventually, the skirting boards rotted away, which we first noticed a few years ago.  More recently, we noticed the ants, so I pulled off the sides and saw the bottom frame members are extensively rotted around about half the spa.

The top rails of the frame are fine.  Most of the bottom rails would need to be replaced.  Some of the vertical supports are looking a little soft on the bottom and would have to be braced if not replaced.  The ants also nested in the foam insulation.  The remnants of the ant colony would have to be dug out of the foam, and I'd patch it with Great Stuff.

Is this worth trying to fix? 

[Tman122]

If you repair it with new wood will the rest of the tub last? PVC and plastic get brittle over time, control systems and pumps fail. This is really a crap shoot.

If you enjoy doing this kind of stuff, tip it up on it's side and go at it. The cost will be minimal.

Make sure to tip it up on the equipment compartment side.

[Spatech_tuo]

If you repair it with new wood will the rest of the tub last? PVC and plastic get brittle over time, control systems and pumps fail. This is really a crap shoot.

If you enjoy doing this kind of stuff, tip it up on it's side and go at it. The cost will be minimal.

Agreed, the cost will be minimal, its mostly just your labor so if you're a DIYer then go for it assuming the spa is otherwise in good/serviceable working order.

[Red MC]

Thanks for the responses.  I am handy, but I have little time these days.  My wife and I both work full time and have to babysit our two kids who are stuck home due to COVID-19.

To clarify, this would be a temporary fix, to get us through the COVID-19 shortages.  We do want a new spa.

Aside from the frame rot and ants in the foam, the spa is fine.  We've had it for 16-17 years, and only had to replace a heater in that time.  The "skin" of the rubber headrests is de-laminating and coming off.  That's the only cosmetic issue.  And some kind of plastic film came out of the "pillow fall" headrest a year or two ago.  It originally created a nice laminar waterfall, but without the plastic film it's now a bit more splashy.  That's the only functional issue, and it's something we don't care about.

The main reason for wanting to buy new is to get something bigger.  We sometimes have other families with kids over, so we'd like something that we can comfortably fit 3-4 adults and 3-4 kids into.  Our current model fits 7, but the seventh "seat" is just the step in.

[Spatech_tuo]

Well right now if you want a new spa there are super long waits.

I suggest you visit your local dealers to see what might be available and when. With that info in hand you'll probably decide to do the temporary fix on your current working spa while waiting.

[Red MC]

Yeah, we've contacted some dealers and the projected delivery dates for a new order range from Oct/Nov to next year.  I suspect that current projected delivery dates reflect best case scenarios, and the way COVID-19 is going, I expect that they will move to the right.  If we order now, we're probably looking at mid-winter delivery.  In this part of the country, that could be inconvenient.  After discussing it with my wife, we're probably going to order now/soon anyway, just to get into the production queue.  We thought about waiting until spring, but there's no guarantee that wait times will be any shorter then.

So I'm going to attempt a temporary makeshift repair/reinforcement that minimizes the risk of leaving it unusable.  I'm not going to tilt the spa up on its side because I'm not sure the damaged frame will retain it's structural integrity.  To tilt it, I'd need to drag it off the neoprene pad by about a foot in order for the back edge to clear the privacy fence when tilting, and then the weakened front bottom frame members would be a fulcrum taking the whole weight of the spa during the tilt. 

Instead, my plan is to leave it in its current position.  I'll use a sawzall to cut out a rotted bottom frame rail in between adjacent vertical frame members, and put a new pressure treated board in its place.  I'll glue and screw reinforcing studs onto the sides of the vertical members, each new stud resting on the new bottom rail segment, and use angle brackets to fasten the new lumber together.  And I'll repeat that for all the damaged sections.  It's not a long-term fix, because I'll still be leaving some rotted wood in place at the bottom of each vertical member, but the load can be taken up by the new lumber.  I'm hoping that plain old pressure treated 2x4s can be used for most of it.  If I have to rip some boards to fit, that will be difficult since I don't have a table saw.

Again, thanks for the replies, and I'll probably start a new thread on XL spa options.