Most seam allowances are 3/8".

 

The idea of letting a jacket (suit coat? blazer?) out makes me very nervous. I will bet good money that you will not be happy with the results. I'd be very surprised if the old pressing lines and the old stitching lines did not show. Maybe you could get away with working on nothing but the two side seams, under the arms, but I'd still be nervous. You'll pour time, money, and energy into an effort with a high chance of unacceptable results.

 

The idea of letting a jacket (suit coat? blazer?) out makes me very nervous. I will bet good money that you will not be happy with the results. I'd be very surprised if the old pressing lines and the old stitching lines did not show. Maybe you could get away with working on nothing but the two side seams, under the arms, but I'd still be nervous. You'll pour time, money, and energy into an effort with a high chance of unacceptable results.

There's no need to be paranoid. Old pressing lines and stitching lines would show with cotton, but not wool. I've done it before without a problem, I just need to know how much fabric I have to work with.

 

Matt hit the nail on the head. So did P and P.

Right on both accounts.

 

its easy. just feel the seam. there is 1/4 inch needed on each side on each side of the line of stitching. thats what holds the seam together.
any cloth more than that is what you have to let out.
in other words. if there is a total of one inch across the whole seam, subtract 1/2 inch for the seams that leaves a 1/2 inch of increase at that seam.
some seams will have more to be let out, and some will have nothing extra available.

now put on the jacket try to bring the two fronts together as you want the jacket to feel. even if you cant quite bring the fronts together.
now measure the gap between the button and buttonhole. thats how much you need to let out.
that distance is measured from the center of the button to the round key hole on the buttonhole.

 

This also works on the more common alteration of taking-in. Overlap the button side with the button hole side. Holding your finger gently on the rounded edge of the keyhole opening, release the flap and measure from your finger to the center of the button. Alex may agree that tacking all vents shut before either test ensures a better measure.

 

its easy. just feel the seam. there is 1/4 inch needed on each side on each side of the line of stitching. thats what holds the seam together.
any cloth more than that is what you have to let out.
in other words. if there is a total of one inch across the whole seam, subtract 1/2 inch for the seams that leaves a 1/2 inch of increase at that seam.
some seams will have more to be let out, and some will have nothing extra available.

now put on the jacket try to bring the two fronts together as you want the jacket to feel. even if you cant quite bring the fronts together.
now measure the gap between the button and buttonhole. thats how much you need to let out.
that distance is measured from the center of the button to the round key hole on the buttonhole.

I have a little over an inch and a quarter across the centre back seam. I'll have to check the side seams. The problem I have is that it pulls a little across the back, but the front fits fine. I can button it at the front without it pulling. So if it can be let out half an inch total I think that might be enough.

 

Then you would want to take the sides out unevenly, If you have, say 1/2" to play with, total, at the sides, you would keep the front where it is and let out just the back, i. e., new thread would go through the existing holes of the front, but out 1/4" on the back, follow? (Not that you're impaired, but my writing may be.). You haven't mentioned vents. They make it sticky when altering the back seam; more so with the sides if twin vented.

 

Then you would want to take the sides out unevenly, If you have, say 1/2" to play with, total, at the sides, you would keep the front where it is and let out just the back, i. e., new thread would go through the existing holes of the front, but out 1/4" on the back, follow? (Not that you're impaired, but my writing may be.). You haven't mentioned vents. They make it sticky when altering the back seam; more so with the sides if twin vented.

Indeed there are double vents. Can the centre back seam be used instead? I've had coats taken in at the centre back that came out very well, but can they be let out there too?

 

I just found this posted by a tailor a few years ago here about taking in a jacket:

Taking in the sides of an off the rack jacket:

The most common alteration on a jacket seems to be the sleeve length, but we have beat that one to death.

The second is altering the sides. the easiest way is to take in the center back seam, but that only works well is when the customer has a narrow back and a flat seat, and that does not happen very often. So, let's take a look at some of the different possibilities...

If taking in the centre back seam only works when one has a narrow back and flat seat, would letting it out there be best for me because I have a wide back and large seat? That's what causes my problems.

 

Hello, Matt

I had two suits let out in the back a few years ago. My tailor used all of the seams including the center to achieve the right shape. Something to bear in mind is that some material that extends into the shoulder (around the pit on the back or dorsal side) may be need to be taken out as well.

May I ask what exactly are you trying to achieve or what is needed? If you are attempting to flatten the back so it is less tapered you "might" have enough material and will not have to touch or worry about the vents if the bottom flares out. However, if you need more room so you can actually hug a date for example I think you may need to see a tailor to check.

Either way good luck!

 

Didn't want to create a new thread. I have a question about letting out the back. Take a look at the example below:


How much would it cost in general to do this? Is this a hard alteration to do? Secondly, I bought a suit that fits well everywhere, but it's tight in the back just like the photo. However, it has a windowpane pattern. Would letting out the upper back look weird/be difficult because of the windowpane design? I'm afraid it would no longer match up if I let out the back.

 

Have no idea as to cost, but as for it being difficult, nah. Not nearly as rough as creating side adjuster tabs to RTW pants, as someone here currently is plotting. That would be a tailoring bad dream. Little skill needed for center seam let-out tho. Remember the lining has to be let out too. As to matching the window pane pattern, you're only interested in meeting the horizontal lines of the pane, the verticals may narrow and widen, similar to a dart.

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Alex P, "a Tailor", who played a major part in this thread when it was created four years ago is no longer active here, but is very much alive at 89 and still tailoring in Chicago. We corresponded a few months ago. I miss him. Elsewhere here, a tribute thread's been created to honor a much-missed member. Mine would be for this man, Alex P., a true old-world Italian tailor who enhanced this forum for many years, sharing hands-on experience in a concise, easy to fathom style, sometimes apologizing for his English, at all times never necessary.

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I was just checking the stats on this little one-page thread with just 10 replies, tho 4 years old, ready? TWENTY-ONE THOUSAND VIEWS. Lordy.

 

Have no idea as to cost, but as for it being difficult, nah. Not nearly as rough as creating side adjuster tabs to RTW pants, as someone here currently is plotting. That would be a tailoring bad dream. Little skill needed for center seam let-out tho. Remember the lining has to be let out too. As to matching the window pane pattern, you're only interested in meeting the horizontal lines of the pane, the verticals may narrow and widen, similar to a dart.

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Alex P, "a Tailor", who played a major part in this thread when it was created four years ago is no longer active here, but is very much alive at 89 and still tailoring in Chicago. We corresponded a few months ago. I miss him. Elsewhere here, a tribute thread's been created to honor a much-missed member. Mine would be for this man, Alex P., a true old-world Italian tailor who enhanced this forum for many years, sharing hands-on experience in a concise, easy to fathom style, sometimes apologizing for his English, at all times never necessary.

Thanks Peak! You've always been very helpful and knowledgeable!

89 and still going strong huh? Good for him. It's great that he still wants to work at that age. That's passion.

 

My tailor charges about $50 CAD for something like this.

 

That should be a fairly simple alteration, and it shouldn't cost too much since it's only one seam. My tailor would probably charge about $35-40.

Funny how since I started this thread I've lost about 30 lbs and have only been taking in jackets!

 

The windowpane at the seam wouldn't match up anymore at the top, near the collar? Would it look strange?

 

The windowpane at the seam wouldn't match up anymore at the top, near the collar? Would it look strange?

I guess it depends on how you loose the seam. If you loose the seam *from the top* all the way down, the pattern will not match for sure. However, if you only loose it, say from two window blocks down, it can preserve the matching between collar/back while loosen up the back for drape. Notice that the back panels are taken in from mid to bottom sides already based on the ways the patterns are shown.

It depends on where you need it to be loosen.

 

My tailor charged me $25-40 for something like this. The result was great for allowing about 3/4-1 inch total.

I have noticed that she will often release the lining of the bottom of the suit with scissors, which allows her access to the seam so see exactly how much fabric she can work with.