How many tons of AC for a home with spray foam insulation?

No good answer for this, most AC guys only go by rule of thumb.

You really need something called a Manual J. If you know all the R factors for your entire house you can try to calculate yourself.

There are some downsides to getting too large of a unit, as they will cycle too quickly and not run long enough to get the humidity out of the home. Sometimes you can lower the fan speed, or get the more modern units that have multiple stages.

I definitely don’t know any of that. Who can do this manual j? Pretty much any hvac contractor?

inspectors are all idiots, never trust them to know what they are doing, never trust their inspections to be thorough, never ever follow their advice on anything.

spray foam should be somewhere between 600-1000sq ft per ton because a lot depends on the type and amount of foam and if it was done properly.

you can turn a home into a mold trap if its not done right and its rarely done right. most i see the homeowner has to go back after the fact and add outdoor air ducts to bring in outside air to stop the mold growth.

call a licensed professional to come out and do an HVAC inspection and indoor air quality assessment

Thanks. Any recs for the Nola area?

You should also factor in number of windows, their orientation, number of occupants, shading by trees, etc. When I built my last house Carrier had software that you could plug the data in and viola. Of course I rounded up.

I would suggest calling Benfatti out of Slidell. They are a good company that will perform a heat load (manual J) on the space and give you a quote based on that assessment. The company I work for does the same, but we don't go across the lake. They do good work.

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someone to do this j manual analysis

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ah ok, im sure someone from your area can help, if not call the local permit and inspection office. they know good people because they often use them for code inspections which are a completely different animal then realtor inspectors

You can buy a dehumidifier for $150 OP and plug it in under your air handler to drain into your hvac drain lines.

As said, there are a lot of parts to the puzzle. The last thing you want is for your house to not cool down. Humidity can be dealt with in other ways though.

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inspectors are all idiots, never trust them to know what they are doing, never trust their inspections to be thorough, never ever follow their advice on anything.

spray foam should be somewhere between 600-1000sq ft per ton because a lot depends on the type and amount of foam and if it was done properly.

you can turn a home into a mold trap if its not done right and its rarely done right. most i see the homeowner has to go back after the fact and add outdoor air ducts to bring in outside air to stop the mold growth.

call a licensed professional to come out and do an HVAC inspection and indoor air quality assessment

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Spot on. As others mentioned if you want to get accurate advice have someone run a manual J. Make sure you find an HVAC company that is familiar with spray foam though. Over-sizing, short cycling and moisture issues should be things they are aware of.

I used spray foam (which was a great investment) but HVAC company didn't think it mattered and just went by their normal "rule of thumb". I took .5 Ton of their recommendations, per a manual J and never had any issues.