Structural Engineering

Ask Structural Engineering Questions and Get Expert Answers ASAP

Ask an Expert,
Get an Answer ASAP!

Structural Engineering

I have sagging 2x 10 floor joist across a 10' section that I

Customer Question
would like to shore up...
I have sagging 2x 10 floor joist across a 10' section that I would like to shore up with a jackpost and an I beam. They are sagging because when the house was built 55 years ago, the plumbers cut 1/2 way through the center beam in 2 places to install bathtub drains. what size steel I-beam (S beam?) would I need
Submitted: 1 year ago.Category: Structural Engineering
Show More
Show Less
Ask Your Own Structural Engineering Question
Answered in 3 hours by:
2/28/2016
Structural Engineer: StructuralEng, Consultant replied 1 year ago
StructuralEng
StructuralEng, Consultant
Category: Structural Engineering
Satisfied Customers: 7,389
Experience: Structural Engineer
Verified

Can I get back to you in the morning?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
I have no answers yet that satisfy my needs
Structural Engineer: StructuralEng, Consultant replied 1 year ago

What exactly is the span of the beam and what will be the joist length on each side of the beam? Will it support any ceramic tile?

I assume this will be supporting this single floor only and nothing else?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
When you say span of the beam are you referring to the joist length or the length of the I-beam? I expect the I beam to take load over 8'2",perhaps 10' at the most. The joist length is 14".from wall to existing basement I beam. The cut joist is cut at 3'10 and 6'8 inches from the wall. Due to the basement layout, I plan to put a jackpost 4'4" from the wall.
Customer reply replied 1 year ago
you are correct, it supports a single floor and of course the roof above
Customer reply replied 1 year ago
there is ceramic tile in both of the bathrooms above, floors and walls with heavy bathtubs
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Is there a wall above where this beam will go? If not then it won't support the roof

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
Good point. Yes, there is a wall, but it is not a load bearing wall...To the I-beam, it is just the weight of the wall
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Thank you. I'm running numbers now.

Ask Your Own Structural Engineering Question
Structural Engineer: StructuralEng, Consultant replied 1 year ago

You can plan for a W5x19 beam ASTM A992 Gr. 50. It's 5" deep x 5" wide and weighs 19 pounds per foot

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
Thinking about it there is a load bearing wall that is above the proposed I-beam. the wall is 8 foot long, and is 5 1/2 foot from the exterior wall. Only 3 foot of it would be above the are projected to have the beam, the other 5 foot would be beyond the edge of the beam
Structural Engineer: StructuralEng, Consultant replied 1 year ago

So right now there is a load bearing wall near the mission of joists? With no wall or beam below the joists at that location? That doesn't sound right. I will size the beam for that if you want me to, but that doesn't sound right. It would be exceptionally uncommon to have a bearing wall load joists and not have a beam or wall below

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
I will make and attaché a pdf to show you what it looks like, perhaps words are failing me
Customer reply replied 1 year ago
maybe this will help. I scribbled out the sagging area that I put down the first time
Customer reply replied 1 year ago
I am stepping away from the computer for about an 60-90 minutes. Not sure if I can see this on my cell phone
Structural Engineer: StructuralEng, Consultant replied 1 year ago

I will assume it's supporting the roof, too. What is the city and state so I can look at snow loading?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
Fairfax VA
Customer reply replied 1 year ago
OK. I am back online now
Structural Engineer: StructuralEng, Consultant replied 1 year ago

W6x20

Ask Your Own Structural Engineering Question
Structural Engineer: StructuralEng, Consultant replied 1 year ago

.

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
This I bean will be supported by only 1 jack stand and the stand will not quite be centered. Does that make a difference?
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Yes. That's completely unstable.

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
I intend to screw the I beam to the joists at the end of the span. Am I just taking the wrong general approach?
Customer reply replied 1 year ago
I have a local engineer who came up with a solution using joist hangers and blocking as close to the end of the cut joist as possible and the 1 joist next to it. This would shore up the cut joist, but that does nothing to restore the sag that it has caused
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Yes. That's relying on the joists to keep it stable. That's not prudent if the load resultant is directly over the post. It will not be, which makes it much worse. Two posts are critical

Ask Your Own Structural Engineering Question
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Exactly. You need two posts for the beam

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
OK, I can do that I think, but I cannot put the posts at the extreme ends of the beam. Perhaps within 2 1/2 foot of the end, but then the beam would have to be 21' long
Structural Engineer: StructuralEng, Consultant replied 1 year ago

21'? I thought the beam only needed to be 10' long maximum. If it's going to be 21' that will make a big difference.

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
Only a 10' cross section of the joists are affected. I cannot put a jackpost at that end though as it is in the middle of the basement floor...Of my woodworking shop where I move large 4x8 sheets and lumber sometimes 12 foot long. I would have to locate the jackpost at the other end wall (not shown in the diagram I sent you) just to get it out of the way. Perhaps I abandon the I-beam idea and as a way of shoring up and eliminating the existing say and just add the additional joist and hangers per my local engineer. Granted it will not fix the sag, but it may be just to hard and expensive to go the I-beam route. Thoughts?
Structural Engineer: StructuralEng, Consultant replied 1 year ago

How much of the joist depth is cut away? Do you have utilities running through the joists?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
The joist has at a 2 " deep by 6 inch long cut an a 3 inch deep by 6 inch long cut in the 2 places I showed you on the drawing I attached earlier the deeper cut is closer to the middle. Those cuts are made so the drain lines can come out of the tubs Also,, right next to that cut is a 2 inch hole where the drain lines go through the joists after they come down and go through their P trap. Would a picture help?
Structural Engineer: StructuralEng, Consultant replied 1 year ago

A picture would be great. Bid the sag only in the couple joists that were notched?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
No, the sag starts 4 joists away and progressively gets worse to the damaged joist - about 1/4 inch more per joist. I do not think the joists are going to fail - they've been like this since the house was built 50 years ago. I would like to stop it from getting worse and eliminate the sag if I can. The attached picture shows the cut joist
Structural Engineer: StructuralEng, Consultant replied 1 year ago

What is the smallest unobstructed dimension from the bottom of the subfloor to the highest obstruction on the side with the highest obstruction at the lowest elevation?

Ask Your Own Structural Engineering Question
Customer reply replied 1 year ago
I'm not trying to be dense, I too am an engineer (electrical), but I do not understand your question. what do you mean by "highest obstruction on the side with the highest obstruction at the lowest elevation?" what are you referring to as an obstruction?
Structural Engineer: StructuralEng, Consultant replied 1 year ago

Anything that would prohibit sistering the joists

Ask Your Own Structural Engineering Question
Ask StructuralEng Your Own Question
StructuralEng
StructuralEng
StructuralEng, Consultant
Category: Structural Engineering
Satisfied Customers: 7,389
7,389 Satisfied Customers
Experience: Structural Engineer

StructuralEng is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

walkereng

walkereng

Consultant

2,613 satisfied customers

Over 30 years of Structural Engineering experience.

vgdlpc

vgdlpc

Master's Degree

17 satisfied customers

Civil Engineer, Major in Structures and Foundations. Professional Engineer 11 years of experience.

StructuralEng

StructuralEng

Consultant

7,389 satisfied customers

Structural Engineer

Matt

Matt

Engineer

40 satisfied customers

Mechanical Engineering Hons degree, been working in automotive industry for the last 18 years - Engine development engineer

ibosley

ibosley

Master's Degree

88 satisfied customers

Mechanical Engineering

Ellen

Ellen

Consultant

109 satisfied customers

attorney and legal researcher

P. Simmons

P. Simmons

Attorney

138 satisfied customers

45 years old, retired Marine Officer, current attorney

< Previous | Next >

Related Structural Engineering Questions
We are building a house. When the framers sheathed the
Hi! We are building a house. When the framers sheathed the walkout basement with osb, I noticed a hole the size of a silver dollar in the osb. Contractor said framer nailed a hole there without a stud… read more
walkereng
walkereng
Consultant
Bachelor's Degree
2,613 satisfied customers
Does putting insulation under the garage floor slab really
Does putting insulation under the garage floor slab really help with the floor temperature? … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I don't have a structural eng. in my immediate area. I am
I don't have a structural eng. in my immediate area. I am wanting to replace a 14 foot section of wall with a beam. The wall is center wall of first floor and sits squarely above the center girder of … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I have and old house with a section of main beam in the
I have and old house with a section of main beam in the basement that is significantly deteriorated. The beam consists of five wood 2 x 10s that span 11 feet between brick columns. I want to replace t… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I want to put a beam in place of a load bearing wall. the
I want to put a beam in place of a load bearing wall. the distance is 10 feet 6 inches … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
What load capacity has a 6X6 wide flange over 20 feet? I
what load capacity has a 6X6 wide flange over 20 feet ? … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I am trying to remove a wall in my house to open up the
I am trying to remove a wall in my house to open up the living room and a back room. and join them. I want to try and size a LVL beam to replace said wall. The house is 36 feet wide. The wall is on th… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I am looking for a steel beam size( structural technician) A
I am looking for a steel beam size( structural technician) … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I am building a window wall in my addition and have been
Good morning I am building a window wall in my addition and have been getting some opinions from framers and looking for your opinion. The wall is 24' wide and 17' to top plate and than gable end not … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
Have an 18 ft. span, exterior wall need to support the
have an 18 ft. span, exterior wall need to support the second floor and roof load, what size laminated beam do I use? … read more
walkereng
walkereng
Consultant
Bachelor's Degree
2,613 satisfied customers
I have a 17 foot opening on outside wall weight bearing roof
I have a 17 foot opening on outside wall weight bearing roof single story room with 20 ft ceiling … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I need to calculate the load-bearing capacity of a steel
I need to calculate the load-bearing capacity of a steel I-Beam 6"x6"x1/4", 13'-6" long supported by 9" masonry on each side… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
Want to double check some calculations. Sizing a lintel for
Sizing a lintel for a masonry opening and the calculations came up with a beam W8 x 13. Want to double check. … read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
A friend of mine has a 200 year old farmhouse with an
A friend of mine has a 200 year old farmhouse with an attached and closed concrete slab porch. I have no idea how all the porches is. It is a block porch with a food Cellar underneath. The slab is app… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
I have a 12' wide x 24' deep garage. The garage door is on
i have a 12' wide x 24' deep garage. The garage door is on the 12' end and this is the gable end. This is a single story building with no storage. The roof is supported by simplet trusses at 24' cente… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
What size beam do I need to span 23' to hold 10' floor
what size beam do I need to span 23' to hold 10' floor joists? I have limited access to the property so I need use 2x lumber to build the beams … read more
walkereng
walkereng
Consultant
Bachelor's Degree
2,613 satisfied customers
I have a about a 16 foot span from top of 8" thick concrete
I have a about a 16 foot span from top of 8" thick concrete wall to top of concrete wall under a floor. I am setting a 800 pound 'aga oven' (english cast iron water jacket oven) in the center of the s… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
Question about applying 1/2" osb over perfectly good
Question about applying 1/2" osb over perfectly good exterior 4x8 sheets of 1977 smooth siding. Should I remove old and install new 1/2" osb to accept new 8" lap siding. Seems crazy to remove old if w… read more
StructuralEng
StructuralEng
Consultant
7,389 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x