Void in HLT and Mash Tank

If you have a void in your HLT and Mash tank how do you compensate for it? When I transfer from my HLT to my Mash tank I am losing quite a bit of wort from the void. When I soak my grains do I add that amount of water on top of my 1.5 gallons per pound of grain?

Thanks

That’s what I do add about a gallon to my water

What you’ve described is known as “deadspace.” First you have to figure out how much you’re losing to deadspace, then add that much extra water to your strike water volume. Keep your water to grist ratio the same. Increase your strike water volume only, not your sparge water volume.