BIAB Limitations?

Sparging will pretty much always give you higher efficiency. But I think most BIABers instead add the strike water +sparge water all at once in their mash. Then, since you are presumably on a burner, you mash out by raising the temp to 165ish and then pull the bag to let it drain. That is basically no sparge.

My problem with sparging BIAB is the best way to do it is to 'teabag' into another pot with sparge water heated in it. I don't have another kettle that can handle the grain so this is virtually impossible for me.

 

if you have a grate or pulley where you don't have to hold the bag constantly you could dump the 'sparge' water over the suspended grain

 

But then you need a grate and/or pulley...
I actually do have a grate but my pot isn't wide enough to pour the sparge water over it without way too much extra effort.

 

If you're going to go through the trouble of setting up some kind of pulley system to suspend your grain bag and then attempt to sparge a hanging bag by hand...you should spend the $40 and 20 min and build a cooler mash tun and be done with it...

 

I don't disagree. I BIAB with no sparge or sometimes sparge in a separate kettle. I do know some BIAB'ers have a pulley or grate already set up to assist in the lifting and draining of the bag though

 

Short answer: If you have a 15 gal kettle, then NO. Simply start with all the water you need for the batch.

As with any brewing method, you can make BIAB as complicated as you want. IMO, the whole point of BIAB is simplicity, shorter brew day, and less equipment. That's why I love it, and I have no plans to expand beyond pure single-vessel BIAB (I have a 15 gal kettle). Once you start adding a sparge step, additional vessels, and/or a pulley rig contraption, why not just do traditional 3-vessel mashing?
As mentioned in posts above, you will likely have lower efficiency than traditional fly sparging, but so what? IMO, chasing after high efficiencies on a homebrew scale is a waste of energy. Sure, it's cool for bragging rights. But if I have to add another pound of base malt to get an equivalent OG, then that extra $1.00 per batch isn't worth my time and it doesn't justify additional equipment for me.

Cheers and happy BIAB brewing!

 

You could use the mash efficency predictor tab in BrewCipher. Enter your original recipe and mash efficiency (with sparge) on the Recipe tab. Note your OG. Go to the Mash Efficiency Predictor tab and tell it to convert 'Spage to No-Sparge' which will give you a new (lower) estimated mash efficiency. Go back to the Recipe Tab and enter that new efficiency. Then enter your target OG (OG from original recipe) and click the 'Scale!' button, which will increase your grain bill as needed to hit the OG.

 

Adding more base malt doesn't increase your efficiency, it simply compensates for lower efficiency. How much do you need to compensate? Difficult to say, you really just need to brew a few beers and see what your system does for you.