Engineering Question

[J pold]

I have a engineering question for the CP brain trust. I live in a 1,486 SF house that is very old (built in 1910) and the primary structure of the house, including the foundation is wood. My girlfriend and I are thinking of hosting a Christmas Party and the guest list is roughly 60 people. Assuming 80% are able to make it that’s still 48 people and I have concerns about the houses ability to accommodate that much weight from a structural perspective.

Does anyone know the floor load capacity for old homes? Back in 1910 I don’t think they engineered houses to take on that much weight. I took a look on-line and surprisingly there isn’t much information. Any help or opinions are welcomed.

[bootsnixon]

I suggest you request RSVP's to include guest weight to get a firm handle on this.

[You Need a Thneed]

People don't tend to like to stand close enough together to make this an issue. Your floor almost certainly wouldn't collapse even if you had people standing packed together over the whole room

Seriously, you don't have any issue here.

[Sliver]

Is it a Truman Home?

[GGG]

Back in university we did this at an old 3 story house. The floor flexed at least 6" and it was noticeable from above and below. It didn't break though.

I think the condition of the joists supporting the floor is the most important factor. If you can go to the basement and determine joist spacing, span and size you could compare to current wood standards but that assumes its all in good condition.

[undercoverbrother]

[pseudoreality]

I'm not a structural engineer, but I do coordinate a lot of multi-disciplined projects. A structural engineer would ask you what your joist sizes are, what the spacing is and what the maximum span is. From that, you can look it up on load tables and come up with a maximum number of people per certain sized room. My gut tells me you are probably okay, but if you want a professional opinion you are going to need that info.

[Fuzz]

Back in University we had a big party, I think there were maybe 40 people upstairs at the time. Everyone was dancing and jumping, and we suddenly heard a loud "crack". Never did find any damage, but something definitely went. So uh, don't play any House of Pain and you might be ok?

[You Need a Thneed]

Do you know the size of the joists and the spacing between them? Also how long do they span?

Again, I wouldnt be worried about 50 people. You may notice some slight flex where people are more highly concentrated, but that will be about it.

Modern houses are designed for a minimum of 50 pounds per square foot of live load - ie things that can move (over every square foot of the floor at the same time). If you do the math, it takes a lot of people in a room to "overload" the floor, almost more than can fit in the room. There is safety factor on top of that.

Old codes can't be too much different, or else they would have had problems even moving particularly heavy pieces of furniture across the floor.

If you have a cantilevered balcony, that's different. Don't put 48 people out on one of those.

[calumniate]

Don't stand in the sink, you might void the warranty

[Bill Bumface]

Wannamaker!

[Northendzone]

came in for truman home reference and was rewarded with two.

leaving more than satisfied - thanks CP

[rohara66]

Cancel the party!

http://www.dailymail.co.uk/news/arti...use-party.html

[Leeman4Gilmour]

Originally Posted by J pold

I have a engineering question for the CP brain trust. I live in a 1,486 SF house that is very old (built in 1910) and the primary structure of the house, including the foundation is wood. My girlfriend and I are thinking of hosting a Christmas Party and the guest list is roughly 60 people. Assuming 80% are able to make it that’s still 48 people and I have concerns about the houses ability to accommodate that much weight from a structural perspective.

Does anyone know the floor load capacity for old homes? Back in 1910 I don’t think they engineered houses to take on that much weight. I took a look on-line and surprisingly there isn’t much information. Any help or opinions are welcomed.

http://bedroom-workshop.com/workshop...orloading.html

Here's a discussion...In general it looks like most floors are designed to take on 40lbs/sq. ft.


50 people @ 175 lbs = 8750lbs. No mosh pits in an area smaller than 220 sq ft!!



Edit - Thneed beat me....

[Huntingwhale]

Originally Posted by undercoverbrother

[cracher]

Another anecdote to express a cool story bro: had a house in scenic acres (1980s construction). The living room was huge, so I used a 220 gallon fish tank on a heavy rosewood base in the middle to sort of form 2 separate areas. 2 years later, we were playing with marbles and noticed that no matter where you dropped them, they rolled towards the fish tank. Using a laser leveller, we figured that the floor in the middle was a full inch lower than by walls. Good thing I got divorced and lost that house.

[You Need a Thneed]

Originally Posted by cracher

Another anecdote to express a cool story bro: had a house in scenic acres (1980s construction). The living room was huge, so I used a 220 gallon fish tank on a heavy rosewood base in the middle to sort of form 2 separate areas. 2 years later, we were playing with marbles and noticed that no matter where you dropped them, they rolled towards the fish tank. Using a laser leveller, we figured that the floor in the middle was a full inch lower than by walls. Good thing I got divorced and lost that house.

About 1800 lbs of water alone in that tank. Remove the tank, and the floor likely springs back up.

[flamesfan1297]

Originally Posted by Sliver

Is it a Truman Home?

How are they supposed to know he didn't get a bunch of guests to stand on the floor?

[flamesfan1297]

But seriously, your good. The floor won't break

[OMG!WTF!]

If you want, and if it works out with your basement, grab some 2x4's and build a supporting wall or two across the joists in the basement.It's not hard or expensive. Some old houses might have a problem holding that many people.