OT Workshop A/C BTUs needed

Seeking opinion on needed size of A/C unit for husband's shop. Please tell me what we need: 6,000... 8,000 or 10,000 BTU's.

Online calculator says square footage is just a hair more than than recommeded for a 6,000-8,000 BTU machine (small shop at 414 sq. ft., it is an old hog house)...so it is recommending a 10,000 BTU unit.

BUT I am wondering... would a 6,000 window unit actually do a good job at both cooling and removing moisture? [*Note: willing to spend more on an 8K or 10K BTU A/C if needed - but don't want to get too large a unit as then it may not run enough draw the moisture out of the air. Do not want a cold but damp shop. Plus smaller units are lighter for handling purposes).

Wondering because of the following factors:

1. Ceiling height is only at 7 feet (so this means less cubic feet than a taller building).
2. Ceiling and walls are well insulated.
3. Most windows that face the sun are shaded by two open lean-to's that we added on for shade on south and west of the building.
4. There is also a very large shade tree just west of the shop - so it protects from much of the late afternoon sun.

Thanks if you can help with advice.

By my calculation you need 7245 BTU's to cool.

It seems to me that the 5 or 6 Mbtu are only suitable for small bedrooms etc. We bought a 5 a few years ago for our son and after one week exchanged it for an 8, world of difference! My shop is 300 sq. ft. with a 9 foot ceiling and very well insulated, and a 8 does a good job. It also depends where you are and how often you open the door!

Brother built a new house that was always hot
and uncomfortable...complained to A/C installer
who said:"it's sized right for the Square feet"
I'd rather have a large unit loafing, and be cool
than a smaller unit working to death/can't keep
up/doing a poor job!

I should of used K for thousand instead of M! I got to think kilograms! And I can't figure out how to edit!

Thanks for the replies guys. Sounds like we should go with the 8K then. Kinda thought it, but we wanted some other opinions (and sales staff will often tell you to buy what is more expensive whether needed or not).

We had tried a 6K out there last week... but it is 10 years old - so it was not a good unit to make a judgement call on.

never under size an ac unit you will only live to regret it,most recommendations are a perfect world scenarios,had a 36k unit that was supposed to sufficient for the size house it was installed in, always struggled to keep up on hot days especially if there was very much traffic in and out of the house ,contrary to recommendations i installed a 48k end of problems even on 100 degree days

Some of us who are on the threshold of being classified "elderly" remember when they rated air conditioners by "tons". So this lady goes into a dealer and ask for an AC unit of so many tons. The dealer says, Mam' we now rate them in BTUs. She thought a minute and replied. "Well, I need one with enough BTUs to cool a BUT about the size of a TUB!