How to suspend ceiling joist from rafters above

Reply

  #1  
Old 11-08-04, 03:36 PM
lbeach
Visiting Guest
Posts: n/a
Question How to suspend ceiling joist from rafters above

I would like to remove a low hanging beam from the middle of my living room. Above the ceiling is attic space the total span is 25 feet the beam is across the middle where the 2 X 8 ceiling joists overlap. I have been told that the 2 X 12 rafters above can support the ceiling weight and All I need to do is nail 1X8 spruce boards on either side of the rafters and the joists on both sides of the beam to hold the ceiling in place. I it seems to make sense to me I just need some unbiased opinion from this board.

Thanks in advance.
 
  #2  
Old 11-08-04, 10:17 PM
Doug Aleshire's Avatar
Member
Join Date: Feb 2002
Location: United States
Posts: 4,679
Received 0 Votes on 0 Posts
lbeach,

"Above the ceiling is attic space the total span is 25 feet the beam is across the middle where the 2 X 8 ceiling joists overlap. I have been told that the 2 X 12 rafters above can support the ceiling weight and All I need to do is nail 1X8 spruce boards on either side of the rafters and the joists on both sides of the beam to hold the ceiling in place."

Unsure if an "unbiased opinion" is needed here or someone professional to really look at what you have to determine what can be done. Depending on who you talked to, your question seems to be more of acquiring reassurance that it can be done. I have provided a link to one project that I have done this to but not be the method you describe.

http://dougaphs.smugmug.com/gallery/279304

The issue is what size is the beam that is there now? Removing it would not be advised as the 2x12's are not there to support roof and ceiling. This would be too heavy a load. If the beam was not needed, it wouldn't be there. You are talking about structural integrity being compromised and I venture to say, your ceiling will be sagging or worse. The 2x12's are there due to total span that was required for your roof system, most likely. The option would be to raise this beam, if feasible and use metal joist hangers.

Again I stress a professional to assess this.

I am assuming that the span of this area is 12'-6", not the entire 25'. The picture that I provided is a span of 16' feet using 3 - 1 3/4" x 11 7/8" LVL beams with metal joist hangers. As you can tell by the finished pictures, it is not even seen at the point of existing structure tied into the new. The procedure to do this is to build temp walls to hold up both sides of the ceiling while cutting the existing 2x8's and then inserting a new beam to accommodate the load it will be carriying. This would require some manpower, raising new supports on each of the beam and patching in the area. Building permit should be acquired for this of which plans should be submitted.

Hope this helps!
 
  #3  
Old 11-08-04, 10:36 PM
L
Member
Join Date: Mar 2000
Location: Arlington, WA
Posts: 9,238
Received 0 Votes on 0 Posts
If I'm following you, this beam is under the center of the 2X8 ceiling joists, and those joists overlap above the beam. NO WAY do you remove that beam and try to sister 2X12's along the joists!!

You call in a structural engineer. He (or she) will evaluate everything involved, INCLUDING snow and wind loads (you haven't told us where you live) and can determine IF the beam can go away, and if so, HOW.
 
  #4  
Old 11-09-04, 11:17 AM
H
Banned. Rule And/Or Policy Violation
Join Date: Jul 2004
Posts: 463
Received 0 Votes on 0 Posts
Both previous posters are Correct

Both previous posters are correct.

Doug in that what he described as a possible solution for your problem is to install a 'blind header' which in essence is a beam that is paced ABOVE the ceiling to bear the weight of the joists.

Lefty because he rightly stated that splicing joists cannot be done.

(Both fellows were correct on other points as well)

What I'd like to add is that nailing a 1x8 to a rafter and to its corresponding joist below is NOT an adequate means of either supporting the ceiling joists, nor is it acceptable since it also compromises the load bearing ability of the rafters above.

As both previously mentioned, you need an on site professional to examine the structure and suggest adequate modifications which should then be approved by you code office.

But to offer a simplistic answer to your original question:

You CANNOT suspend ceiling joists from rafters above under most conditions and in most instances.
 

Last edited by homebild; 11-09-04 at 11:37 AM.
  #5  
Old 11-10-04, 06:59 AM
lbeach
Visiting Guest
Posts: n/a
Smile Thank you for all your input

Thanks you have gave me a lot of food for thought. I must say that the solution I got was from an engineer. I was calling to see what was needed to be done and suggest that this was a common practice. He informed me that I should not need an engineering stamp to do this. This is why I posted the question. I was trying to guage how common this practice is. I would say not very common on this board. Maybe around here in Mass. it is. I remember 20 years ago that I build a house with 12 X 20 bed room up stairs. It was supposed to be two bed rooms we just left out the wall. Back then they just nailed 2X4 scabs from the ridge pole down to the ceiling joists. I believe that the roof rafters were no more than 2X12 and the pitch was minimal 1 over 12. (GAMBREL roof Full shed dorma on the back). That passed all inspections and the test of time. I must say that I am not happy with the builder and feel he has gone a long way in over building this house. He was supposed to hire an architect ect.. Well I saw some drawings of the outside but never saw any framing plans. This build has been a big mistake right from the very begining on all kinds of levels. Anyway thanks again for all your input. I guess I will pay the money for the piece of mind and have someone else come out and look at this.
 
  #6  
Old 11-10-04, 07:14 AM
Doug Aleshire's Avatar
Member
Join Date: Feb 2002
Location: United States
Posts: 4,679
Received 0 Votes on 0 Posts
lbeach,

With what you describe about that home 20 years ago, "Back then they just nailed 2X4 scabs from the ridge pole down to the ceiling joists."

I want to stress one thing, this was for roof support only, not one in which you support roof and ceiling joists. I would hope you looked at what I provided for some insight as to what should be done, at least one example of it.

Since you say you had an engineer telling you what is "OK", I do question why you would even ask this Forum what we think if you received "professional" advice?

What I know as well as Lefty and Homebild for example, we have many years of qualified experienced. For what I do now, I have no choice but to be accurate with my solutions or I would not be in business.

You make me feel better that you will seek others advice by letting them look at what you have. Our hope is that each member gets the best help, whether it be here or what you pursue on your own there locally. We want the best for each and every member! There are circumstances when hiring a professional to give you that peace of mind is the best before tackling something that would be a problem that would cost more to repair. Its better being safe than sorry.

Let us know how you are making out and thanks for filling us in.
 
  #7  
Old 11-10-04, 09:03 AM
lbeach
Visiting Guest
Posts: n/a
Why I asked

The reason I asked was engineer told me that it was common practice. It was advice just passed to me over the phone. He was very nice about it and did not charge me. I explained as best I could giving him the span and lumber sizes and roof pitch. He just shot the answer off without hesitation. One caviot he did mention was that there could not be any living space above the ceiling and I don't think of attic space as living space. It was almost like I should have known this, if you know what I mean. Well the engineer hasn't signed anything so he is not on the hook if this is not O.K. And if it was such common practice then I figured a board like this might be aware of this option and confirm or, in this case dispute, its merits. I have been searching to see if anyone else has done this or has experiance with this type of setup. My guess is with premade trusses being the way to do this. That this old technology is no longer fresh in any ones mind.

One Question if you use joist hangers on the ceiling joists instead of having them over lapped and nailed together. Gravity pulling down on the roof rafters create forces that want to spread the outside walls. The joist hangers are nailed directly into the beam so if the out side walls spread the force of the spreading joists could pull out the nails, couldn't it?



lbeach
 
  #8  
Old 11-10-04, 10:41 AM
Doug Aleshire's Avatar
Member
Join Date: Feb 2002
Location: United States
Posts: 4,679
Received 0 Votes on 0 Posts
lbeach,

I understand and thanks for the clarification.

Your questions is a good one and one that should be answered by having someone look at what you have. The reason that I say this, as long as we don't have any current vertical struts from roof rafters down to the existing beam means that what I proposed would allow for the conversion you inititally described. If they are located on the ceiling joists in areas away from the beam then this is not an issue either. Again we are not touching these.

Ceiling joists are placed horizontally, really isn't any outward force involved here as there is a down load. With what I proposed and it will require someone to confirm, that I am not changing the configuration, if you will.

I am only "raising" the existing beam to a new level to accomodate the flush ceiling. I want the beam to maintain the load of the ceiling joists. We are just attaching them to the beam. The roof rafters are not being touched so the issue of outward force would not be an issue as long as we are not touching them.

This is all on the assumption that the "beam" is there to only support the ceiling system only and nothing else.

One point I want to bring up that the "beam raising" is subject to clearances available at the end of the beam. I am assuming that the ends of the beam are on the "gable" end of the home or in a location that will not inhibite the beam raising concept. This means the total height available from the top plate to the roof sheathing, if I assumed wrong. We want to make sure you have full height for a secure bearing point. Cutting this beam to a taper on the top edge is not recommended at all. Again, without seeing it, I cannot provide you with certainty that the idea is feasible in your case.

Hope this helps!
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: