Bonus room addition cost estimation help

[lowcountrygamecock]

I'm putting my budget together to finish my bonus room upstairs. We left it unfinished when we built the house so it's basically room trusses. I need some help estimating budget so ill know how to plan how much it's going to take. Here are some details. I live in South Carolina. It's 1200 sq feet total split in three rooms, a 100 sq foot office, a 100 sq foot bathroom and 1000 sq foot play room in the middle. I put down what I think it may cost on some of these but I may be way off so correct me if I'm wrong. Nothing fancy at all in any of these rooms.

Electrical=I'm doing the wiring and all electrical work myself. I've already purchased outlets, switches, boxes ect. Just need roughly 1000 feet of wire, a few light fixtures and ceiling fans. $1000 budget

Plumbing= Plumbing the bathroom will take some work because I didn't install plumbing up there up front but I have some professional help and will do most of the labor myself on that part so I plan on figuring the normal cost of a new 100 sq foot bathroom plus $500 for the extra work. I just don't know what that normal cost is. Budget needs to cover small shower, sink, toilet mirror and small vanity. Budget Help?

Carpet= basically carpeting the 1000 foot middle room and will hire out the whole job. Budget help?

Office and bathroom tile = I've done tile work before so this shouldn't be too bad. $1000 budget

Drywall = basically drywall the whole thing. 8 foot ceilings with a knee wall about 6 feet up. This one i have no idea. Budget help?

Paint = same here. Basically prep and paint the whole thing. Three rooms, probably two colors, maybe three. Budget help?

Hvac = I have some connections here and can get close to wholesale price on the unit and all the supplies. I should be able to get a break on labor also. Still don't know what to expect though. 1.5 ton heat pump and air handler. Budget help?

I think that covers it unless you think of something I'm missing. Again I maybe off on some of my estimates so fire away please. Thanks

 

[NUTTSGT]

Carpet= basically carpeting the 1000 foot middle room and will hire out the whole job. Budget help?

Thanks

I'll throw this out there.

Carpet can cost and arm/leg if you buy some stuff. How often do you want to change it or the decor in the room ? It's a playroom, so will it get ruined by spills/stains ?

Consider this. Buy a stock carpet at HD, Menard's or Lowes. Get ahold of the guys that laid your carpet when you built your house and ask them about doing a cash job on the side. You might be surprised how cheap they'll come in on a Saturday morning or evening for a couple of hours to make a few extra bucks.

If you have kids/pets, you might want to be replacing it in 7-8 years, so why spend big bucks for carper that'll likely get some very hard wear by them.

 

[nolimits76]

My 2nd house I owned, I originally had all my living space downstairs and a "stairway to nowhere". It was a custom build home. The builder framed up for knee walls similar to yours and ensured I had floor joists stout enough to hold a pool table (ultimate end game).

Anyhow, fast forward a year or so and I got started on the renovation. I work in construction management and decided to play general contractor. I used one of our Hispanic contacts as my main sub. Our agreement was I'd buy all materials, obtain permits, deal with inspectors, etc. He would bring all labor & tools necessary to complete the work. Both him and his crews were professionals that did this during the day, and my job was simply extra money for them as a moonlighting operation. He ended up doing some minor framing, laying my subfloor, insulation, drywall, paint & trim. I had a plan of what was going to happen and we agreed on price before we began.

A buddy owed me some money and gave me a HVAC system. It still required ducting and some other parts to make it all work. Then a buddy of a buddy did the install. Another professional, but was laid off and did this on the side for cash.

Electrical I subbed out entirely. Plumbing was handled by yet another buddy deal. Parts ordered through a supply house at discount pricing. You will need more than $500. I'd say at least $2,500 or better.

Carpet was installed by the same people that did the bottom level of my house. I want to say it was around $1.50/sf installed.

All in, it cost me about $15k and I added on nearly 800sf. So roughly $19/sf was my cost and my main job was dealing with permits, inspections and clean up between the various stages. It added a boat load of money to my house when I sold it, and was a good overall investment.

FYI, this was about 7 years ago. So inflation needs to be accounted for to some degree.

 

[lowcountrygamecock]

Anybody else?

 

[nolimits76]

I suspect you will be hard pressed to get good solid numbers. Finishes and local competition will determine your true final costs.

If you have a set of plans, I would start visiting with some contractors and get quotes. For the DIY stuff you plan to do, I would look at your plans and do quantity take offs. Once you have an idea of quantities, you can shop a few different vendors. Heck, even some places like Lowe's and HD will take your plans and do the quantity takeoffs and generate a custom quote for you based on what you want. This is pretty common practice in actual contractor lumber yards as well.

I'd source 3 or 4 vendors per quote. Remember, if someone is drastically low, there is a chance you are looking at apples and oranges. When in doubt, re-visit with the vendor and make sure it's a complete scope. There is a difference between being low bidder, and lowest responsible bidder.

 

[larry4406]

When/if you do this, make sure that you properly insulate the space. The radiant heat from the roof is not to be underestimated. Use thermoply or similar on the back side of your knee walls so that the insulation is captured on all six sides.

 

[lowcountrygamecock]

Glad you mentioned that. I forgot to include insulation in my estimations.