Muddskip Level 5 Smooth 3-in-1 Drywall Additive

Muddskip Level 5 Smooth is a powdered 3-in-1 drywall additive that you mix into your own joint compound. It isn't pre-mixed mud, and compound isn't included. It comes in a 2 lb bag or a 5-gallon pail. It handles seams, base coat, and finish coat for a same-day Level 5+ finish.

How to Mix It

One 2 lb bag goes into one typical 18 lb bag, 35 lb box or 4.5-gallon bucket of joint compound. Add water as needed to get the consistency you want. If you're mixing a partial batch, scale the additive down to match.

The 5-gallon pail holds 40 lb of additive and is labeled for 20 batches. Scoop out 2 lb per batch, the same rate as one bag. The 2 lb bag works for a single batch, and the pail makes sense when you're mixing batch after batch.

Same-Day Coats, Wet on Wet

With Muddskip in the mud, you can put the next coat on as soon as the last one is dry to the touch. You don't have to wait for it to dry all the way. To be clear, it doesn't make compound dry faster. It lets you recoat sooner.

Level 5 Smooth is built for a same-day finish. If you are using both formulas together, tape the seams with Heavy Duty and let them dry to the touch, which takes about 90 minutes depending on conditions. Then run Heavy Duty over the wall, and finish with Level 5 Smooth.

Sanding

No sanding is necessary unless you want to. Dried coats can be rehydrated and retooled instead of sanded flat. If you do sand, use nothing coarser than 150 grit, and 220 to 320 is preferred. All-purpose compound used as a finish coat can sand harder, so keep that in mind when you pick your mud.

Picking the Compound

• Midweight: good for every coat
• Lightweight: for the final one or two thin, tight finish coats
• All-purpose: taping, bedding, blocking, filling and heavy repairs only, not finish coats

You can mix Muddskip into premixed compound or into setting-type compound. Don't combine setting-type and premixed in the same system unless current technical guidance says it's OK.

Bonding and Surfaces

On many substrates, you won't need a separate primer or bonding agent. That isn't true of every surface. Wallpapered or unknown surfaces may still need a sealer or primer first.

Smooth vs Heavy Duty

Smooth vs Heavy Duty, built for every finish. They're two different formulas, not two sizes of the same product.

• Level 5 Smooth: seams, base coat, finish coat, and a same-day Level 5+ finish
• Heavy Duty: seams, base coat, finish coat, and a same-day Level 3–4 finish, plus heavy repairs and textures

Muddskip Heavy Duty is the matching formula when the job needs a Level 3–4 finish, heavy repairs, or texture work.

Before You Start

Keep the room between 55°F and 95°F (13–35°C) for 24 hours before finishing and while you work. Results depend on your compound, conditions, substrate and technique, so try it on a small area before you take it to a big job. It's a powder, so control dust when you mix or sand. The Smooth safety data sheet (SDS) is on the technical data page.

Going for a full skim? Our Level 5 finish guide and drywall finishing levels guide cover what each level takes. You'll find more mixes in our mud additives collection.