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67
votes
12answers
35k views

Is there a case where nails are better than screws, from an engineering/structural standpoint?

Is there a case where nails are better than screws, from a structural standpoint? For instance: Say you used screws instead of nails on a backyard deck, when the design specifically called for nails. ...
30
votes
4answers
9k views

Are there ways to determine if a wall is load bearing?

Other than looking up blue prints, which many homeowners may not have, are there ways to determine if a wall is load bearing? Methods I can think of might include: Going up in the attic to check if ...
15
votes
1answer
10k views

Is my rapidly failing foundation dangerous?

I'll be succinct. I'm afraid we're having a full structural failure. Over the past week, crack after crack has been appearing in our plaster and walls. I'm honestly concerned for our safety. Our ...
14
votes
3answers
2k views

Is notching a flange on an I-Joist ever acceptable?

My home builder said that the following notch in a flange on an I-Joist was acceptable, but I've read that you're never supposed to do so. Is that true?
12
votes
5answers
28k views

How do I improve Pergola Stability?

The deck is nearly finished but I have a small structural problem with the pergola. A left or right force near the top of the pergola (such a a tall person leaning on the post) leads to a bit of ...
9
votes
2answers
3k views

Is joist sag at connection with header a problem?

I am having the ceiling in the finished part of my basement redone, and have it fully open now. I can see the connection of the joists to the headers have given somewhat, as the house is 85 years old ...
9
votes
1answer
3k views

How do I know if it is safe to remove a wall?

When looking at a wall, how can I tell if I can safely remove it?
8
votes
1answer
1k views

How can I safely remove and replace a wall?

The Wall: This is about 25' long, and it separates my kitchen from my living room/Dining room. Underneath it, we have a double 2x8 floor joist, which is supported midway on an 8 inch steel I-beam. ...
7
votes
2answers
3k views

What are these beams for in my loft?

I have very good building experience but in a house we bought recently I have been wondering what the heck to do with my loft. Initially its converted to a mini workshop / storage The max height is 1....
7
votes
2answers
20k views

What size ceiling joists and rafters should I use for a 14' span?

I'm going to build a single story addition to my home with a width of 14ft. I plan on using ceiling joists every 16" but I'm not sure which size to get. The roof will be asphalt shingles and the attic ...
6
votes
1answer
2k views

Should I worry about sagging joists?

I have a two story house and some of the joists between the floors are sagging about an inch or two. When I walk around upstairs I can feel the level difference and downstairs you can slightly see the ...
6
votes
1answer
6k views

Can I safely make a door frame taller?

UPDATE: April 22 What I ended up doing was removing the trim non-destructively. Above the door frame, it was clearly not load bearing, so I continued and was not so non-destructive. The end-result ...
6
votes
1answer
386 views

Designed a floating corner table, unsure of its potential strength. Any ideas?

I pretty much want to attach some angle iron to the studs and some threaded rods to the angle iron. I'll rout out the profile of the angle iron into the butcher block so it sits flush and so that when ...
5
votes
2answers
88 views

How to go about building an aquarium into a wall?

I plan to install a 180 gallon aquarium in my basement. The dimensions are 72" x 24" x 25" About 2000 pounds after sand and decorations when filled How should I go about doing this without having ...
5
votes
4answers
3k views

How do I deal with a joist in the way of where I need to run a pipe?

I'm in the process of installing central vac lines (2" OD) in a finished house, and I am trying to run a line into the upstairs hallway. I have removed drywall in the garage below and drilled a hole ...
5
votes
2answers
4k views

What should I do about this load bearing wall that is only supported by a joist floor?

My floors pitch in the same spots as they do on the 1st and 2nd floors. My home was built in the 1890's. I have some soft spots in the basement joists and added 4x4" posts to each side of the main ...
5
votes
2answers
441 views

How can I stop a porch crack from causing internal cracking?

My front porch slab has cracked and part is at least an inch lower. It is supporting the roof. Now there is a crack going up the inside of my drywall at the same place. Suggestions on how to solve ...
4
votes
3answers
2k views

How can I choose the best lag screw / lag bolt?

I will be fastening Unistrut vertically along studs to facilitate garage storage, and want some guidance on choosing the "best" lag bolts to use. I want them large enough to handle hundreds of pounds ...
4
votes
2answers
4k views

14ft Ceiling beam sagging 5/8" - what to do?

First some background: Our home is a 2 story detached. On the main floor it is entirely open concept, with a ~14' drywalled horizontal support beam separating the kitchen from the living room area. ...
4
votes
2answers
10k views

How much sagging is considered normal for floors in old (100+ years) houses?

I am currently looking at a house in New England that dates back to the 1820's that has a sagging floor in the living room. The floor dips down about one inch near one of the walls and I was told by ...
4
votes
2answers
320 views

How should I run Cat5e cable between rafters?

I've got cathedral ceilings with no attic space and 2x8 rafters. There is no space to run wiring without going through the rafters. At the moment I've got my eaves open for an unrelated problem and ...
4
votes
1answer
922 views

Can a load bearing beam be offset from lapping joists?

I'm replacing a section of 4'' load bearing wall by a large 8''x8'' steel beam, and due to the size of the beam it would stick out to one side too much if I were to install it exactly centered with ...
4
votes
1answer
6k views

How far can I move ceiling joists up?

The second floor of our house has a fairly low ceiling, perhaps 6'8" or 6'10". The width of the structure is only about 16' with standard construction and the ceiling joists running parallel to to the ...
3
votes
1answer
901 views

When will drilling through wall members affect structural integrity?

When can you freely drill medium to large sized holes in studs or door jambs, and when do you need to be concerned about damaging the structural integrity of the structure?
3
votes
3answers
640 views

What is the right way to mount a support column to a deck and to a header?

Situation: I have an existing deck with a roof overhang. I'm in the process of planning a rebuild and need to detail how the columns will A: attach to the existing roof and B: to the deck. I can find ...
3
votes
2answers
58 views

Is a double 2x4 beam adequate for a 64" opening?

I am opening my dining room and I don't want to compromise the structural integrity. The previous entryway was supported by two 2"x8". The new entryway is supported by two 2"x4". The new support is ...
3
votes
1answer
1k views

What is involved in enlarging a concrete garage door opening?

I have a concrete garage with an opening measuring 99" wide by 85" high. There is 10" of concrete from the door opening to the left and right walls and about 1' above. All walls are 8" thick and ...
3
votes
2answers
349 views

Floating wall mounted office desk

I'm currently about to embark on redeveloping my home office. We have a room with a small alcove and want to mount a desk top inside it. The approx size is 220cm x 80cm We can source the wood we ...
3
votes
1answer
2k views

How can I permanently fix a sagging floor?

I have a home I purchased roughly 18 months ago. The house is a traditional 2 story cape code (3BR 1BA) and is structurally very sound and extremely stable. However, on the primary floor of the house,...
3
votes
1answer
129 views

Should my chimney sit on my roof?

I am renting a house built in the 1940s. The mortar around the brick was cracked causing leaks. Someone had built a chimney around the outside of the original chimney. So outside it's twice the size ...
3
votes
1answer
227 views

Front House Posts Not Resting on Anything

I have 5 roof support posts that are supposed to be resting on concrete blocks but one of them is not even touching the concrete block and the other 4 have some separation from the concrete block. ...
3
votes
2answers
1k views

Are there span tables published for repairing a cut roof joist?

A roofing company mistakenly cut a 2 foot section out of a roof joist, on my home. I'm seeking a reference to what would constitute a proper repair, preferably a prescriptive code or a load table. ...
3
votes
0answers
60 views

How can I reduce the bounciness of a floor? [duplicate]

My apartment is on the second floor of a low-rise building. There are no units directly under it; the apartment sits above the open-air garage. I feel basically everything that my next door ...
2
votes
3answers
683 views

What size beam do I need, and can I build one from lumber and steel?

I want to support a 20 ft. span of my roof where two roofs come together. My house is was originally 46'by 20'. A 40'by 12' addition was added, making an L shape, and when they put the beam in they ...
2
votes
2answers
131 views

Structural cross joists and load-bearing walls (century home)

I have a friend that recently took possession of a century home. Its a 4 plex and He was told it was an old school house (at least at some point in time). We’re experienced weekend warriors but ...
2
votes
1answer
3k views

Replacing rot in wooden porch column

I have a porch column which has some rot at the bottom. These are smaller porch columns similar to http://www.homedepot.com/p/Unbranded-6-in-x-6-in-x-8-ft-Pine-Porch-Column-709721/202087424. I've ...
2
votes
2answers
2k views

Fixing a sagging foundation

We are currently renting our house and considering purchasing it from the owner, but it is sagging, and in some rooms it is rather significant and noticeable, with the worst parts being approximately ...
2
votes
1answer
12k views

How can I calculate the yield strength of steel tube?

There's a lot of information -- and even some debates -- on which has a stronger yield strength between square and round steel tube. The majority points to square when the dimensions are equal at the ...
2
votes
1answer
113 views

What kind of board can span 16 ft for a wall pergola

We are building a wall pergola that we want wisteria to grow on top of. The pergola will only come about 3.5-4 ft out from the wall (Edit: the columns themselves are less than 2ft from the wall). I ...
2
votes
1answer
461 views

Remove closet center support beam?

I have a bump-out closet in an addition. It had two sets of bi-fold doors, separated by a beam in the middle. The beam seems to bare very little load, and I'd like to remove it for one continuous ...
2
votes
1answer
139 views

What is the difference between LVL 1.9 and 2.0?

A structural engineer gave me a header design using beams made from LVL 1.9. Looking around, I'm seeing more LVL 2.0 available locally. What is the difference?
2
votes
3answers
487 views

Is it safe to shave off 1/8" from a load-bearing stud?

I am trying to install a small metal media cabinet in a load-bearing wall in my basement, but unfortunately the cabinet is about 1/8" too wide to fit between the studs. Is it safe to shave off a ...
2
votes
2answers
204 views

What's the point of a thin (1/4" width) piece of wood set diagonally between two studs?

What's the point of a thin (1/4" width, ~2-3" wide) piece of wood set diagonally between two studs? I just took out a piece of drywall for some other work I'm doing, and between two studs, there's ...
2
votes
2answers
25 views

ceiling joist storage expression

I have pre made truss ceiling joist in the garage. The joists are 2x4x21'. I want to use space above the joists for storage. I want to sister a 2x6x21' or 2x8x21' next to 2x4x21' is this ok? If ...
2
votes
1answer
169 views

Can it be appropriate to orient a 2x4 “wide side out”?

When we frame walls, we normally orient the 2x4 with the thin surface facing outward. What are the consequences of orienting the 2x4 so that the wide surface faces outward instead? Does the wood ...
2
votes
2answers
649 views

Ceiling cracks appear and worsen over weeks. Self repair or professional?

Background We recently purchased a home built in mid-50s. At the time, no structural movement or displacement was noted by the home inspector. Over the last few weeks, there have been long cracks on ...
2
votes
2answers
14k views

Can I get away with 5/4“ cedar decking across a 24” span in a children's play structure?

I am currently in the process of designing/building a play structure for my son. The structure will include a 5' high elevated deck, that is 6'x4'. The supports for the decking will be 24" center-to-...
2
votes
1answer
107 views

How can I fix composite deck railing that wasn't installed with brackets?

Had a contractor install a composite railing on my deck and he did not use brackets to secure the railings he just screwed it to the posts. This was 3 years ago, it looked great at first but, over the ...
2
votes
1answer
166 views

Floor joist attachment improvements in presence of existing ledger?

TL;DR: AFAIK there are no joist hangers that can be retrofit in a location where there's an existing ledger board without removing said ledger, right? Is there anything I should think about aside ...
2
votes
1answer
206 views

Proper backfill for a trench dug below foundation level (within the 45 degree cone of support)

Given a trench dug below foundation level, what's the proper way to backfill? Here I'm talking about a trench below the bottom edge of an unreinforced concrete foundation built in 1950, supporting a ...