Brewing our first Imp Stout...

Grain bill looks pretty good at first glance. I do not see some of the information I would like.
Est FG? Mash temp? Fermentation temp?
90% efficence seems ambitious but it is your system so you should know better than I.
I would double the IBU's but that is me, plus I dont know your est FG.
Never used WL1084 but any smack pack alone is underpitching for OG99 so you better get familiar with starters and use Mr Malty to help you along.
I have little experience with spices, but when I made my holiday porter last year I used the vodka extract method at kegging and it worked very well.
Good luck, I love a good RIS.

 

I second the vodka extract. Make sure you ferment lower on the yeast strain temp to get you through high krausen. After that gradually ramp it up to ambient. This will help prevent some of those boozy flavors so you can add them right back in with orange firewater. If you extract, you can also add exactly how much you want. I think I used 1 oz of sweet orange peel and a few oz of vodka when I make my Imp. It's VERY orangy after a year.

Another piece of advice would be to stay sanitary. It's especially important if you're going to cellar a beer. You want to make sure you don't get an infection, as over time, this will really have a big impact on your beer.

 

I would say, if it all possible, add your flavor additions in secondary and do a split batch (with half the beer remaining unflavored). My experience has been that if jump in to a new style/recipe and make a bunch of additions, it makes things harder to troubleshoot if you're not happy. With a split batch, you'll at least have a decent idea of whether you might have an issue with the base beer or one of your additions.

 

BTW Nicefly, If you've never used 1084 you're missing out on something big in your life. It smells amazing when you make a starter, even better when you are fermenting, and perfect when it clings to your lip from sipping a dry stout.

 

I may have to try it. I toggle between 1968 and 1728 for most of my brews, American IPA's included.
So many yeast, so little time.

 

So the Wyeast reported attenuation is 71-75%, as in low. If you want this to finish around FG30, or higher, keep the high mash temp. Personally I would do 150 no matter what yeast I was using with something this big.

Starter is better in my opinion. Plenty of info out there.

Get some vodka and take a little out. put your spices into that on brewday and seal it up. dump it into the secondary or add at bottling.

 

Totally agree with this post. You need to get the RIS right before you can get the variants right.

 

You need to do a starter, no question. Consider some way of oxygenating that too, if possible.

For your question about aging, I've never left a beer sitting on its yeast in primary for that long, but that's not to say it can't be done. In my experience, the colder you can age, the quicker it will smooth out. For instance, an imperial stout that we aged at <40*F for 3-4 months was smoother and less harsh than the previous imperial stout we made that aged at ~68*F for 6-8 months.

 

I think 2 oz is fine. I did one. Few month ago, not quite as big but used 2 oz in the boil and added j Nibs at flame out. Also made. Bourbon nib mix I added to secondary with some oak and coffee too. I think your on the right track

 

honestly if you want to make such a big beer as a beginner, buy about 5 packs of dry yeast rehydrate & pitch

nottingham or us-05

 

I agree on the dry yeast.... I mean.. you could do one liquid and the other dry, and rehydrate it, and call it a day and I'd think you'd have PLENTY of yeast for that gravity.

I'm not big on starters, mainly because I don't have the stuff, or the time/will power to make one, so I'll buy all the yeast I need to call it good. I don't brew to be a cheap ass, but some like to keep it as cheap as possible, which is cool, but at the risk of working more.

 

If you have the means, brew a smaller stout first, then brew your RIS on the day you rack the first beer into the secondary. Then you can just put your RIS in the same primary with no need to sanitize and a big fat yeast cake to get you going.

Plus you can test your additions on the first stout.

By the way, IMO dont age the RIS on the yeast. Let it hang out in a secondary for 2-4 months. The yeast cake will start to impart unfriendly flavors after a while.